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Sample records for non-invasive fluoroscopic imaging

  1. Computerized tomography using video recorded fluoroscopic images

    NASA Technical Reports Server (NTRS)

    Kak, A. C.; Jakowatz, C. V., Jr.; Baily, N. A.; Keller, R. A.

    1975-01-01

    A computerized tomographic imaging system is examined which employs video-recorded fluoroscopic images as input data. By hooking the video recorder to a digital computer through a suitable interface, such a system permits very rapid construction of tomograms.

  2. Non-invasive Imaging of Colitis using Multispectral Optoacoustic Tomography.

    PubMed

    Bhutiani, Neal; Grizzle, William E; Galandiuk, Susan; Otali, Denis; Dryden, Gerald W; Egilmez, Nejat K; McNally, Lacey R

    2016-12-01

    Currently, several non-invasive modalities, including MRI and PET, are being investigated to identify early intestinal inflammation, longitudinally monitor disease status, or detect dysplastic changes in patients with inflammatory bowel disease (IBD). Here, we assess the applicability and utility of multispectral optoacoustic tomography (MSOT) in evaluating the presence and severity of colitis. Mice with bacterial colitis demonstrated a temporally associated increase in mesenteric and colonic vascularity with an increase in mean signal intensity of oxygenated hemoglobin (p=0.004) by MSOT two days after inoculation. These findings were significantly more prominent 7 days after inoculation, with increased mean signal intensity of oxygenated hemoglobin (p=0.0002) and the development of punctate vascular lesions on the colonic surface, which corresponded to changes observed on colonoscopy as well as histology. With improvements in depth of tissue penetration, MSOT may hold potential as a sensitive, accurate, non-invasive imaging tool in evaluation of patients with IBD.

  3. Non-invasive assessment of the liver using imaging

    NASA Astrophysics Data System (ADS)

    Thorling Thompson, Camilla; Wang, Haolu; Liu, Xin; Liang, Xiaowen; Crawford, Darrell H.; Roberts, Michael S.

    2016-12-01

    Chronic liver disease causes 2,000 deaths in Australia per year and early diagnosis is crucial to avoid progression to cirrhosis and end stage liver disease. There is no ideal method to evaluate liver function. Blood tests and liver biopsies provide spot examinations and are unable to track changes in function quickly. Therefore better techniques are needed. Non-invasive imaging has the potential to extract increased information over a large sampling area, continuously tracking dynamic changes in liver function. This project aimed to study the ability of three imaging techniques, multiphoton and fluorescence lifetime imaging microscopy, infrared thermography and photoacoustic imaging, in measuring liver function. Collagen deposition was obvious in multiphoton and fluorescence lifetime imaging in fibrosis and cirrhosis and comparable to conventional histology. Infrared thermography revealed a significantly increased liver temperature in hepatocellular carcinoma. In addition, multiphoton and fluorescence lifetime imaging and photoacoustic imaging could both track uptake and excretion of indocyanine green in rat liver. These results prove that non-invasive imaging can extract crucial information about the liver continuously over time and has the potential to be translated into clinic in the assessment of liver disease.

  4. Non-invasive diagnostic imaging of colorectal liver metastases

    PubMed Central

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-01-01

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs. PMID:26217455

  5. Non-invasive diagnostic imaging of colorectal liver metastases.

    PubMed

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-07-28

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

  6. Advances in non-invasive imaging of intracranial vascular disease.

    PubMed Central

    Jäger, H. R.; Grieve, J. P.

    2000-01-01

    Intra-arterial catheter angiography has, in the past, been the mainstay for the investigation of intracranial vascular disease. It is, however, invasive, usually requires in-patients admission, and is associated with a rate of neurological complications between 1% and 3%. In recent years, magnetic resonance angiography (MRA) and CT angiography (CTA) have emerged as non-invasive alternatives for imaging blood vessels and have made a significant impact on neuroradiological investigations. It is the purpose of this article to explain the basic technical principles of these two methods and to give an overview of their current clinical applications. PMID:10700757

  7. Fluoroscopic image-guided intervention system for transbronchial localization

    NASA Astrophysics Data System (ADS)

    Rai, Lav; Keast, Thomas M.; Wibowo, Henky; Yu, Kun-Chang; Draper, Jeffrey W.; Gibbs, Jason D.

    2012-02-01

    Reliable transbronchial access of peripheral lung lesions is desirable for the diagnosis and potential treatment of lung cancer. This procedure can be difficult, however, because accessory devices (e.g., needle or forceps) cannot be reliably localized while deployed. We present a fluoroscopic image-guided intervention (IGI) system for tracking such bronchoscopic accessories. Fluoroscopy, an imaging technology currently utilized by many bronchoscopists, has a fundamental shortcoming - many lung lesions are invisible in its images. Our IGI system aligns a digitally reconstructed radiograph (DRR) defined from a pre-operative computed tomography (CT) scan with live fluoroscopic images. Radiopaque accessory devices are readily apparent in fluoroscopic video, while lesions lacking a fluoroscopic signature but identifiable in the CT scan are superimposed in the scene. The IGI system processing steps consist of: (1) calibrating the fluoroscopic imaging system; (2) registering the CT anatomy with its depiction in the fluoroscopic scene; (3) optical tracking to continually update the DRR and target positions as the fluoroscope is moved about the patient. The end result is a continuous correlation of the DRR and projected targets with the anatomy depicted in the live fluoroscopic video feed. Because both targets and bronchoscopic devices are readily apparent in arbitrary fluoroscopic orientations, multiplane guidance is straightforward. The system tracks in real-time with no computational lag. We have measured a mean projected tracking accuracy of 1.0 mm in a phantom and present results from an in vivo animal study.

  8. Non-invasive Optical Molecular Imaging for Cancer Detection

    NASA Astrophysics Data System (ADS)

    Luo, Zhen

    Cancer is a leading cause of death worldwide. It remains the second most common cause of death in the US, accounting for nearly 1 out of every 4 deaths. Improved fundamental understanding of molecular processes and pathways resulting in cancer development has catalyzed a shift towards molecular analysis of cancer using imaging technologies. It is expected that the non-invasive or minimally invasive molecular imaging analysis of cancer can significantly aid in improving the early detection of cancer and will result in reduced mortality and morbidity associated with the disease. The central hypothesis of the proposed research is that non-invasive imaging of changes in metabolic activity of individual cells, and extracellular pH within a tissue will improve early stage detection of cancer. The specific goals of this research project were to: (a) develop novel optical imaging probes to image changes in choline metabolism and tissue pH as a function of progression of cancer using clinically isolated tissue biopsies; (b) correlate changes in tissue extracellular pH and metabolic activity of tissues as a function of disease state using clinically isolated tissue biopsies; (c) provide fundamental understanding of relationship between tumor hypoxia, acidification of the extracellular space and altered cellular metabolism with progression of cancer. Three novel molecular imaging probes were developed to detect changes in choline and glucose metabolism and extracellular pH in model systems and clinically isolated cells and biopsies. Glucose uptake and metabolism was measured using a fluorescence analog of glucose, 2-NBDG (2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose), while choline metabolism was measured using a click chemistry analog of choline, propargyl choline, which can be in-situ labeled with a fluorophore Alexa-488 azide via a click chemistry reaction. Extracellular pH in tissue were measured by Alexa-647 labeled pHLIP (pH low insertion peptide

  9. Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis

    PubMed Central

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

    2014-01-01

    Autoimmune pancreatitis (AIP) is characterized by obstructive jaundice, a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate, with or without a pancreatic mass. Type 1 AIP is the pancreatic manifestation of an IgG4-related systemic disease and is characterized by elevated IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic lesions. Type 2 AIP usually has none or very few IgG4-positive plasma cells, no serum IgG4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement. AIP is diagnosed in approximately 2%-6% of patients that undergo pancreatic resection for suspected pancreatic cancer. There are three patterns of autoimmune pancreatitis: diffuse disease is the most common type, with a diffuse, “sausage-like” pancreatic enlargement with sharp margins and loss of the lobular contours; focal disease is less common and manifests as a focal mass, often within the pancreatic head, mimicking a pancreatic malignancy. Multifocal involvement can also occur. In this paper we describe the features of AIP at ultrasonography, computed tomography, magnetic resonance and positron emission tomography/computed tomography imaging, focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma. It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients. Non-invasive imaging plays also an important role in therapy monitoring, in follow-up and in early identification of disease recurrence. PMID:25493001

  10. Estimating Trabecular Bone Mechanical Properties From Non-Invasive Imaging

    NASA Technical Reports Server (NTRS)

    Hogan, Harry A.; Webster, Laurie

    1997-01-01

    An important component in developing countermeasures for maintaining musculoskeletal integrity during long-term space flight is an effective and meaningful method of monitoring skeletal condition. Magnetic resonance imaging (MRI) is an attractive non-invasive approach because it avoids the exposure to radiation associated with X-ray based imaging and also provides measures related to bone microstructure rather than just density. The purpose of the research for the 1996 Summer Faculty Fellowship period was to extend the usefulness of the MRI data to estimate the mechanical properties of trabecular bone. The main mechanical properties of interest are the elastic modulus and ultimate strength. Correlations are being investigated between these and fractal analysis parameters, MRI relaxation times, apparent densities, and bone mineral densities. Bone specimens from both human and equine donors have been studied initially to ensure high-quality MR images. Specimens were prepared and scanned from human proximal tibia bones as well as the equine distal radius. The quality of the images from the human bone appeared compromised due to freezing artifact, so only equine bone was included in subsequent procedures since these specimens could be acquired and imaged fresh before being frozen. MRI scans were made spanning a 3.6 cm length on each of 5 equine distal radius specimens. The images were then sent to Dr. Raj Acharya of the State University of New York at Buffalo for fractal analysis. Each piece was cut into 3 slabs approximately 1.2 cm thick and high-resolution contact radiographs were made to provide images for comparing fractal analysis with MR images. Dual energy X-ray absorptiometry (DEXA) scans were also made of each slab for subsequent bone mineral density determination. Slabs were cut into cubes for mechanical using a slow-speed diamond blade wafering saw (Buehler Isomet). The dimensions and wet weights of each cube specimen were measured and recorded. Wet weights

  11. Fluoroscopic tumor tracking for image-guided lung cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Lin, Tong; Cerviño, Laura I.; Tang, Xiaoli; Vasconcelos, Nuno; Jiang, Steve B.

    2009-02-01

    Accurate lung tumor tracking in real time is a keystone to image-guided radiotherapy of lung cancers. Existing lung tumor tracking approaches can be roughly grouped into three categories: (1) deriving tumor position from external surrogates; (2) tracking implanted fiducial markers fluoroscopically or electromagnetically; (3) fluoroscopically tracking lung tumor without implanted fiducial markers. The first approach suffers from insufficient accuracy, while the second may not be widely accepted due to the risk of pneumothorax. Previous studies in fluoroscopic markerless tracking are mainly based on template matching methods, which may fail when the tumor boundary is unclear in fluoroscopic images. In this paper we propose a novel markerless tumor tracking algorithm, which employs the correlation between the tumor position and surrogate anatomic features in the image. The positions of the surrogate features are not directly tracked; instead, we use principal component analysis of regions of interest containing them to obtain parametric representations of their motion patterns. Then, the tumor position can be predicted from the parametric representations of surrogates through regression. Four regression methods were tested in this study: linear and two-degree polynomial regression, artificial neural network (ANN) and support vector machine (SVM). The experimental results based on fluoroscopic sequences of ten lung cancer patients demonstrate a mean tracking error of 2.1 pixels and a maximum error at a 95% confidence level of 4.6 pixels (pixel size is about 0.5 mm) for the proposed tracking algorithm.

  12. Retinal functional imager (RFI): non-invasive functional imaging of the retina.

    PubMed

    Ganekal, S

    2013-01-01

    Retinal functional imager (RFI) is a unique non-invasive functional imaging system with novel capabilities for visualizing the retina. The objective of this review was to show the utility of non-invasive functional imaging in various disorders. Electronic literature search was carried out using the websites www.pubmed.gov and www.google.com. The search words were retinal functional imager and non-invasive retinal imaging used in combination. The articles published or translated into English were studied. The RFI directly measures hemodynamic parameters such as retinal blood-flow velocity, oximetric state, metabolic responses to photic activation and generates capillary perfusion maps (CPM) that provides retinal vasculature detail similar to flourescein angiography. All of these parameters stand in a direct relationship to the function and therefore the health of the retina, and are known to be degraded in the course of retinal diseases. Detecting changes in retinal function aid early diagnosis and treatment as functional changes often precede structural changes in many retinal disorders.

  13. Non-Invasive Molecular Imaging of Disease Activity in Atherosclerosis

    PubMed Central

    Dweck, Marc R; Aikawa, Elena; Newby, David E; Tarkin, Jason; Rudd, James; Narula, Jagat; Fayad, Zahi A.

    2016-01-01

    Major focus has been placed on the identification of vulnerable plaques as a means of improving the prediction of myocardial infarction. However, this strategy has recently been questioned on the basis that the majority of these individual coronary lesions do not in fact go on to cause clinical events. Attention is therefore shifting to alternative imaging modalities that might provide a more complete pan-coronary assessment of the atherosclerotic disease process. These include markers of disease activity with the potential to discriminate between patients with stable burnt-out disease that is no longer metabolically active and those with active atheroma, faster disease progression and increased risk of infarction. This review will examine how novel molecular imaging approaches can provide such assessments, focusing on inflammation and microcalcification activity, the importance of these processes to coronary atherosclerosis and the advantages and challenges posed by these techniques. PMID:27390335

  14. Non-invasive imaging of skin cancer with fluorescence lifetime imaging using two photon tomography

    NASA Astrophysics Data System (ADS)

    Patalay, Rakesh; Talbot, Clifford; Alexandrov, Yuriy; Munro, Ian; Breunig, Hans Georg; König, Karsten; Warren, Sean; Neil, Mark A. A.; French, Paul M. W.; Chu, Anthony; Stamp, Gordon W.; Dunsby, Christopher

    2011-07-01

    Multispectral fluorescence lifetime imaging (FLIM) using two photon microscopy as a non-invasive technique for the diagnosis of skin lesions is described. Skin contains fluorophores including elastin, keratin, collagen, FAD and NADH. This endogenous contrast allows tissue to be imaged without the addition of exogenous agents and allows the in vivo state of cells and tissues to be studied. A modified DermaInspect® multiphoton tomography system was used to excite autofluorescence at 760 nm in vivo and on freshly excised ex vivo tissue. This instrument simultaneously acquires fluorescence lifetime images in four spectral channels between 360-655 nm using time-correlated single photon counting and can also provide hyperspectral images. The multispectral fluorescence lifetime images were spatially segmented and binned to determine lifetimes for each cell by fitting to a double exponential lifetime model. A comparative analysis between the cellular lifetimes from different diagnoses demonstrates significant diagnostic potential.

  15. A novel marker enhancement filter (MEF) for fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Peshko, Olesya; Davidson, Timothy N.; Modersitzki, Jan; Terlaky, Tamás; Moseley, Douglas J.

    2014-03-01

    To enhance the measurements of radio-opaque cylindrical fiducial markers in low contrast x-ray and fluoroscopic images, a novel nonlinear marker enhancement filter (MEF) has been designed. It was primarily developed to assist in automatic initialization of a tracking procedure for intra-fraction organ motion analysis in fluoroscopic sequences. Conventional procedures were not able to provide sufficient improvement due to the complications of noise, small marker size, cylindrical shape and multiple orientations, intensity variations of the background, and the presence of overlaying anatomical measurements in this application. The proposed MEF design is based on the principles of linear scale space. It includes measures that assess the probability of each pixel to belong to a marker measurement, morphological operations, and a novel contrast enhancement function for standardization of the filter output. The MEF was tested on fluoroscopic images of two phantoms and three prostate patients, and was shown to perform better or comparable to the existing filters in terms of marker enhancement and background suppression, while performing significantly better in marker shape preservation.

  16. Non-invasive imaging using reporter genes altering cellular water permeability

    NASA Astrophysics Data System (ADS)

    Mukherjee, Arnab; Wu, Di; Davis, Hunter C.; Shapiro, Mikhail G.

    2016-12-01

    Non-invasive imaging of gene expression in live, optically opaque animals is important for multiple applications, including monitoring of genetic circuits and tracking of cell-based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatiotemporal resolution. However, existing MRI reporter genes based on metalloproteins or chemical exchange probes are limited by their reliance on metals or relatively low sensitivity. Here we introduce a new class of MRI reporters based on the human water channel aquaporin 1. We show that aquaporin overexpression produces contrast in diffusion-weighted MRI by increasing tissue water diffusivity without affecting viability. Low aquaporin levels or mixed populations comprising as few as 10% aquaporin-expressing cells are sufficient to produce MRI contrast. We characterize this new contrast mechanism through experiments and simulations, and demonstrate its utility in vivo by imaging gene expression in tumours. Our results establish an alternative class of sensitive, metal-free reporter genes for non-invasive imaging.

  17. Imaging and finite element analysis: a methodology for non-invasive characterization of aortic tissue.

    PubMed

    Flamini, Vittoria; Creane, Arthur P; Kerskens, Christian M; Lally, Caitríona

    2015-01-01

    Characterization of the mechanical properties of arterial tissues usually involves an invasive procedure requiring tissue removal. In this work we propose a non-invasive method to perform a biomechanical analysis of cardiovascular aortic tissue. This method is based on combining medical imaging and finite element analysis (FEA). Magnetic resonance imaging (MRI) was chosen since it presents relatively low risks for human health. A finite element model was created from the MRI images and loaded with systolic physiological pressures. By means of an optimization routine, the structural material properties were changed until average strains matched those measured by MRI. The method outlined in this work produced an estimate of the in situ properties of cardiovascular tissue based on non-invasive image datasets and finite element analysis.

  18. Hyperspectral imaging coupled with chemometric analysis for non-invasive differentiation of black pens

    NASA Astrophysics Data System (ADS)

    Chlebda, Damian K.; Majda, Alicja; Łojewski, Tomasz; Łojewska, Joanna

    2016-11-01

    Differentiation of the written text can be performed with a non-invasive and non-contact tool that connects conventional imaging methods with spectroscopy. Hyperspectral imaging (HSI) is a relatively new and rapid analytical technique that can be applied in forensic science disciplines. It allows an image of the sample to be acquired, with full spectral information within every pixel. For this paper, HSI and three statistical methods (hierarchical cluster analysis, principal component analysis, and spectral angle mapper) were used to distinguish between traces of modern black gel pen inks. Non-invasiveness and high efficiency are among the unquestionable advantages of ink differentiation using HSI. It is also less time-consuming than traditional methods such as chromatography. In this study, a set of 45 modern gel pen ink marks deposited on a paper sheet were registered. The spectral characteristics embodied in every pixel were extracted from an image and analysed using statistical methods, externally and directly on the hypercube. As a result, different black gel inks deposited on paper can be distinguished and classified into several groups, in a non-invasive manner.

  19. Characterization of the Tumor Microenvironment and Tumor–Stroma Interaction by Non-invasive Preclinical Imaging

    PubMed Central

    Ramamonjisoa, Nirilanto; Ackerstaff, Ellen

    2017-01-01

    Tumors are often characterized by hypoxia, vascular abnormalities, low extracellular pH, increased interstitial fluid pressure, altered choline-phospholipid metabolism, and aerobic glycolysis (Warburg effect). The impact of these tumor characteristics has been investigated extensively in the context of tumor development, progression, and treatment response, resulting in a number of non-invasive imaging biomarkers. More recent evidence suggests that cancer cells undergo metabolic reprograming, beyond aerobic glycolysis, in the course of tumor development and progression. The resulting altered metabolic content in tumors has the ability to affect cell signaling and block cellular differentiation. Additional emerging evidence reveals that the interaction between tumor and stroma cells can alter tumor metabolism (leading to metabolic reprograming) as well as tumor growth and vascular features. This review will summarize previous and current preclinical, non-invasive, multimodal imaging efforts to characterize the tumor microenvironment, including its stromal components and understand tumor–stroma interaction in cancer development, progression, and treatment response. PMID:28197395

  20. Cryo-balloon catheter localization in fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Kurzendorfer, Tanja; Brost, Alexander; Jakob, Carolin; Mewes, Philip W.; Bourier, Felix; Koch, Martin; Kurzidim, Klaus; Hornegger, Joachim; Strobel, Norbert

    2013-03-01

    Minimally invasive catheter ablation has become the preferred treatment option for atrial fibrillation. Although the standard ablation procedure involves ablation points set by radio-frequency catheters, cryo-balloon catheters have even been reported to be more advantageous in certain cases. As electro-anatomical mapping systems do not support cryo-balloon ablation procedures, X-ray guidance is needed. However, current methods to provide support for cryo-balloon catheters in fluoroscopically guided ablation procedures rely heavily on manual user interaction. To improve this, we propose a first method for automatic cryo-balloon catheter localization in fluoroscopic images based on a blob detection algorithm. Our method is evaluated on 24 clinical images from 17 patients. The method successfully detected the cryoballoon in 22 out of 24 images, yielding a success rate of 91.6 %. The successful localization achieved an accuracy of 1.00 mm +/- 0.44 mm. Even though our methods currently fails in 8.4 % of the images available, it still offers a significant improvement over manual methods. Furthermore, detecting a landmark point along the cryo-balloon catheter can be a very important step for additional post-processing operations.

  1. A REVIEW OF NON-INVASIVE IMAGING METHODS AND APPLICATIONS IN CONTAMINANT HYDROGEOLOGY RESEARCH

    SciTech Connect

    Werth, Charles J.; Zhang, Changyong; Brusseau, M. L.; Oostrom, Martinus; Baumann, T.

    2010-03-08

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. The most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma-radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods’ advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  2. A review of non-invasive imaging methods and applications in contaminant hydrogeology research.

    PubMed

    Werth, Charles J; Zhang, Changyong; Brusseau, Mark L; Oostrom, Mart; Baumann, Thomas

    2010-04-01

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. Four of the most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods' advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  3. Scanning superlens microscopy for non-invasive large field-of-view visible light nanoscale imaging

    NASA Astrophysics Data System (ADS)

    Wang, Feifei; Liu, Lianqing; Yu, Haibo; Wen, Yangdong; Yu, Peng; Liu, Zhu; Wang, Yuechao; Li, Wen Jung

    2016-12-01

    Nanoscale correlation of structural information acquisition with specific-molecule identification provides new insight for studying rare subcellular events. To achieve this correlation, scanning electron microscopy has been combined with super-resolution fluorescent microscopy, despite its destructivity when acquiring biological structure information. Here we propose time-efficient non-invasive microsphere-based scanning superlens microscopy that enables the large-area observation of live-cell morphology or sub-membrane structures with sub-diffraction-limited resolution and is demonstrated by observing biological and non-biological objects. This microscopy operates in both non-invasive and contact modes with ~200 times the acquisition efficiency of atomic force microscopy, which is achieved by replacing the point of an atomic force microscope tip with an imaging area of microspheres and stitching the areas recorded during scanning, enabling sub-diffraction-limited resolution. Our method marks a possible path to non-invasive cell imaging and simultaneous tracking of specific molecules with nanoscale resolution, facilitating the study of subcellular events over a total cell period.

  4. Diagnostic and prognostic utility of non-invasive imaging in diabetes management

    PubMed Central

    Barsanti, Cristina; Lenzarini, Francesca; Kusmic, Claudia

    2015-01-01

    Medical imaging technologies are acquiring an increasing relevance to assist clinicians in diagnosis and to guide management and therapeutic treatment of patients, thanks to their non invasive and high resolution properties. Computed tomography, magnetic resonance imaging, and ultrasonography are the most used imaging modalities to provide detailed morphological reconstructions of tissues and organs. In addition, the use of contrast dyes or radionuclide-labeled tracers permits to get functional and quantitative information about tissue physiology and metabolism in normal and disease state. In recent years, the development of multimodal and hydrid imaging techniques is coming to be the new frontier of medical imaging for the possibility to overcome limitations of single modalities and to obtain physiological and pathophysiological measurements within an accurate anatomical framework. Moreover, the employment of molecular probes, such as ligands or antibodies, allows a selective in vivo targeting of biomolecules involved in specific cellular processes, so expanding the potentialities of imaging techniques for clinical and research applications. This review is aimed to give a survey of characteristics of main diagnostic non-invasive imaging techniques. Current clinical appliances and future perspectives of imaging in the diagnostic and prognostic assessment of diabetic complications affecting different organ systems will be particularly addressed. PMID:26131322

  5. Mouse models in neurological disorders: applications of non-invasive imaging.

    PubMed

    Waerzeggers, Yannic; Monfared, Parisa; Viel, Thomas; Winkeler, Alexandra; Jacobs, Andreas H

    2010-10-01

    Neuroimaging techniques represent powerful tools to assess disease-specific cellular, biochemical and molecular processes non-invasively in vivo. Besides providing precise anatomical localisation and quantification, the most exciting advantage of non-invasive imaging techniques is the opportunity to investigate the spatial and temporal dynamics of disease-specific functional and molecular events longitudinally in intact living organisms, so called molecular imaging (MI). Combining neuroimaging technologies with in vivo models of neurological disorders provides unique opportunities to understand the aetiology and pathophysiology of human neurological disorders. In this way, neuroimaging in mouse models of neurological disorders not only can be used for phenotyping specific diseases and monitoring disease progression but also plays an essential role in the development and evaluation of disease-specific treatment approaches. In this way MI is a key technology in translational research, helping to design improved disease models as well as experimental treatment protocols that may afterwards be implemented into clinical routine. The most widely used imaging modalities in animal models to assess in vivo anatomical, functional and molecular events are positron emission tomography (PET), magnetic resonance imaging (MRI) and optical imaging (OI). Here, we review the application of neuroimaging in mouse models of neurodegeneration (Parkinson's disease, PD, and Alzheimer's disease, AD) and brain cancer (glioma).

  6. Non-invasive multimodal functional imaging of the intestine with frozen micellar naphthalocyanines

    NASA Astrophysics Data System (ADS)

    Zhang, Yumiao; Jeon, Mansik; Rich, Laurie J.; Hong, Hao; Geng, Jumin; Zhang, Yin; Shi, Sixiang; Barnhart, Todd E.; Alexandridis, Paschalis; Huizinga, Jan D.; Seshadri, Mukund; Cai, Weibo; Kim, Chulhong; Lovell, Jonathan F.

    2014-08-01

    There is a need for safer and improved methods for non-invasive imaging of the gastrointestinal tract. Modalities based on X-ray radiation, magnetic resonance and ultrasound suffer from limitations with respect to safety, accessibility or lack of adequate contrast. Functional intestinal imaging of dynamic gut processes has not been practical using existing approaches. Here, we report the development of a family of nanoparticles that can withstand the harsh conditions of the stomach and intestine, avoid systemic absorption, and provide good optical contrast for photoacoustic imaging. The hydrophobicity of naphthalocyanine dyes was exploited to generate purified ∼20 nm frozen micelles, which we call nanonaps, with tunable and large near-infrared absorption values (>1,000). Unlike conventional chromophores, nanonaps exhibit non-shifting spectra at ultrahigh optical densities and, following oral administration in mice, passed safely through the gastrointestinal tract. Non-invasive, non-ionizing photoacoustic techniques were used to visualize nanonap intestinal distribution with low background and remarkable resolution, and enabled real-time intestinal functional imaging with ultrasound co-registration. Positron emission tomography following seamless nanonap radiolabelling allowed complementary whole-body imaging.

  7. Simulation system for understanding the lag effect in fluoroscopic images.

    PubMed

    Tanaka, Rie; Kawashima, Hiroki; Ichikawa, Katsuhiro; Matsubara, Kosuke; Iida, Hiroji; Sanada, Shigeru

    2013-07-01

    Real-time tumor tracking in external radiotherapy can be achieved by diagnostic (kV) X-ray imaging with a dynamic flat-panel detector (FPD). It is crucial to understand the effects of image lag for real-time tumor tracking. Our purpose in this study was to develop a lag simulation system based on the image lag properties of an FPD system. Image lag properties were measured on flat-field images both in direct- and indirect-conversion dynamic FPDs. A moving target with image lag was simulated based on the lag properties in all combinations of FPD types, imaging rates, exposure doses, and target speeds, and then compared with actual moving targets for investigation of the reproducibility of image lag. Image lag was simulated successfully and agreed well with the actual lag as well as with the predicted effect. In the indirect-conversion FPD, a higher dose caused greater image lag on images. In contrast, there were no significant differences among dose levels in a direct-conversion FPD. There were no relationships between target speed and amount of image blurring in either type of FPD. The maximum contour blurring and the rate of increase in pixel value due to image lag were 1.1 mm and 10.0 %, respectively, in all combinations of imaging parameters examined in this study. Blurred boundaries and changes in pixel value due to image lag were estimated under various imaging conditions with use of the simulation system. Our system would be helpful for a better understanding of the effects of image lag in fluoroscopic images.

  8. Non-invasive imaging using reporter genes altering cellular water permeability

    PubMed Central

    Mukherjee, Arnab; Wu, Di; Davis, Hunter C.; Shapiro, Mikhail G.

    2016-01-01

    Non-invasive imaging of gene expression in live, optically opaque animals is important for multiple applications, including monitoring of genetic circuits and tracking of cell-based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatiotemporal resolution. However, existing MRI reporter genes based on metalloproteins or chemical exchange probes are limited by their reliance on metals or relatively low sensitivity. Here we introduce a new class of MRI reporters based on the human water channel aquaporin 1. We show that aquaporin overexpression produces contrast in diffusion-weighted MRI by increasing tissue water diffusivity without affecting viability. Low aquaporin levels or mixed populations comprising as few as 10% aquaporin-expressing cells are sufficient to produce MRI contrast. We characterize this new contrast mechanism through experiments and simulations, and demonstrate its utility in vivo by imaging gene expression in tumours. Our results establish an alternative class of sensitive, metal-free reporter genes for non-invasive imaging. PMID:28008959

  9. Non-invasive measurements of granular flows by magnetic resonance imaging

    SciTech Connect

    Nakagawa, M.; Altobelli, S.A.; Caprihan, A.; Fukushima, E.; Jeong, E.K.

    1993-01-20

    Magnetic Resonance Imaging (MRI) was used to measure granular-flow in a partially filled, steadily rotating, long, horizontal cylinder. This non-invasive technique can yield statistically averaged two-dimensional concentrations and velocity profiles anywhere in the flow of suitable granular materials. First, rigid body motion of a cylinder fill with granular material was studied to confirm the validity of this method. Then, the density variation of the flowing layer where particles collide and dilate, and the depth of the flowing layer and the flow velocity profile were obtained as a function of the cylinder rotation rate.

  10. A servo-mechanical load frame for in situ, non-invasive, imaging of damage development

    SciTech Connect

    Breunig, T.M.; Nichols, M.C.; Gruver, J.S.; Kinney, J.H.; Haupt, D.L.

    1993-12-31

    The X-ray tomographic microscope (XTM) is a non-invasive X-ray imaging instrument for characterizing a material`s structure three-dimensionally with microscopic spatial resolution. The authors have designed a servomechanical load frame for use with the XTM which will allow imaging of samples under load. The load frame is capable of generating tensile or compressive forces up to 15.6 kN with a design system stiffness of 8.76 {times} 10{sup 8} N/m. The test specimen can be rotated through 360{degree}, without induced bending or torque. Torqueless motion is accomplished by synchronously rotating the grips on precision bearings with an accuracy of 0.01{degree}. With this load frame it will be possible, for the first time, to image the initiation and accumulation of internal damage (0.5 {mu}m detectability) formed in a 6 mm diameter specimen during the application of a monotonic or low frequency cyclic load. This is accomplished by interrupting the test and maintaining a fixed load (or displacement) during the non-invasive XTM data collection procedure. This paper describes the in situ load frame design and experimental capabilities. This system can be used to enhance the understanding of failure in composite materials.

  11. Non-invasive imaging of flow and vascular function in disease of the aorta

    PubMed Central

    Whitlock, Matthew C.; Hundley, W. Gregory

    2015-01-01

    With advancements in technology and a better understanding of human cardiovascular physiology, research as well as clinical care can go beyond dimensional anatomy offered by traditional imaging and investigate aortic functional properties and the impact disease has on this function. Linking the knowledge of the histopathological changes with the alterations in aortic function observed on noninvasive imaging results in a better understanding of disease pathophysiology. Translating this to clinical medicine, these noninvasive imaging assessments of aortic function are proving to be able to diagnosis disease, better predict risk, and assess response to therapies. This review is designed to summarize the various hemodynamic measures that can characterize the aorta, the various non-invasive techniques, and applications for various disease states. PMID:26381770

  12. Non-invasive detection of murals with pulsed terahertz reflected imaging system

    NASA Astrophysics Data System (ADS)

    Yuan, Minjie; Sun, Wenfeng; Wang, Xinke; Ye, Jiasheng; Wang, Sen; Zhang, Qunxi; Zhang, Yan

    2015-11-01

    Pulsed terahertz reflected imaging technology has been expected to have great potential for the non-invasive analysis of artworks. In this paper, three types of defects hidden in the plaster used to simulate the cases of defects in the murals, have been investigated by a pulsed terahertz reflected imaging system. These preset defects include a circular groove, a cross-shaped slit and a piece of "Y-type" metal plate built in the plaster. With the terahertz reflective tomography, information about defects has been determined involving the thickness from the surface of sample to the built-in defect, the profile and distribution of the defect. Additionally, three-dimensional analyses have been performed in order to reveal the internal structure of defects. Terahertz reflective imaging can be applied to the defect investigation of the murals.

  13. Insights into Parkinson's disease models and neurotoxicity using non-invasive imaging

    SciTech Connect

    Sanchez-Pernaute, Rosario; Jenkins, Bruce G.; Isacson, Ole

    2005-09-01

    Loss of dopamine in the nigrostriatal system causes a severe impairment in motor function in patients with Parkinson's disease and in experimental neurotoxic models of the disease. We have used non-invasive imaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (MRI) to investigate in vivo the changes in the dopamine system in neurotoxic models of Parkinson's disease. In addition to classic neurotransmitter studies, in these models, it is also possible to characterize associated and perhaps pathogenic factors, such as the contribution of microglia activation and inflammatory responses to neuronal damage. Functional imaging techniques are instrumental to our understanding and modeling of disease mechanisms, which should in turn lead to development of new therapies for Parkinson's disease and other neurodegenerative disorders.

  14. Non-invasive long-term fluorescence live imaging of Tribolium castaneum embryos.

    PubMed

    Strobl, Frederic; Stelzer, Ernst H K

    2014-06-01

    Insect development has contributed significantly to our understanding of metazoan development. However, most information has been obtained by analyzing a single species, the fruit fly Drosophila melanogaster. Embryonic development of the red flour beetle Tribolium castaneum differs fundamentally from that of Drosophila in aspects such as short-germ development, embryonic leg development, extensive extra-embryonic membrane formation and non-involuted head development. Although Tribolium has become the second most important insect model organism, previous live imaging attempts have addressed only specific questions and no long-term live imaging data of Tribolium embryogenesis have been available. By combining light sheet-based fluorescence microscopy with a novel mounting method, we achieved complete, continuous and non-invasive fluorescence live imaging of Tribolium embryogenesis at high spatiotemporal resolution. The embryos survived the 2-day or longer imaging process, developed into adults and produced fertile progeny. Our data document all morphogenetic processes from the rearrangement of the uniform blastoderm to the onset of regular muscular movement in the same embryo and in four orientations, contributing significantly to the understanding of Tribolium development. Furthermore, we created a comprehensive chronological table of Tribolium embryogenesis, integrating most previous work and providing a reference for future studies. Based on our observations, we provide evidence that serosa window closure and serosa opening, although deferred by more than 1 day, are linked. All our long-term imaging datasets are available as a resource for the community. Tribolium is only the second insect species, after Drosophila, for which non-invasive long-term fluorescence live imaging has been achieved.

  15. Non-invasive intravital imaging of cellular differentiation with a bright red-excitable fluorescent protein

    PubMed Central

    Chu, Jun; Haynes, Russell D; Corbel, Stéphane Y; Li, Pengpeng; González-González, Emilio; Burg, John S; Ataie, Niloufar J; Lam, Amy J; Cranfill, Paula J; Baird, Michelle A; Davidson, Michael W; Ng, Ho-Leung; Garcia, K Christopher; Contag, Christopher H; Shen, Kang; Blau, Helen M; Lin, Michael Z

    2014-01-01

    A method for non-invasive visualization of genetically labelled cells in animal disease models with micron-level resolution would greatly facilitate development of cell-based therapies. Imaging of fluorescent proteins (FPs) using red excitation light in the “optical window” above 600 nm is one potential method for visualizing implanted cells. However, previous efforts to engineer FPs with peak excitation beyond 600 nm have resulted in undesirable reductions in brightness. Here we report three new red-excitable monomeric FPs obtained by structure-guided mutagenesis of mNeptune, previously the brightest monomeric FP when excited beyond 600 nm. Two of these, mNeptune2 and mNeptune2.5, demonstrate improved maturation and brighter fluorescence, while the third, mCardinal, has a red-shifted excitation spectrum without reduction in brightness. We show that mCardinal can be used to non-invasively and longitudinally visualize the differentiation of myoblasts and stem cells into myocytes in living mice with high anatomical detail. PMID:24633408

  16. Non-invasive imaging of cellulose microfibril orientation within plant cell walls by polarized Raman microspectroscopy.

    PubMed

    Sun, Lan; Singh, Seema; Joo, Michael; Vega-Sanchez, Miguel; Ronald, Pamela; Simmons, Blake A; Adams, Paul; Auer, Manfred

    2016-01-01

    Cellulose microfibrils represent the major scaffold of plant cell walls. Different packing and orientation of the microfibrils at the microscopic scale determines the macroscopic properties of cell walls and thus affect their functions with a profound effect on plant survival. We developed a polarized Raman microspectroscopic method to determine cellulose microfibril orientation within rice plant cell walls. Employing an array of point measurements as well as area imaging and subsequent Matlab-assisted data processing, we were able to characterize the distribution of cellulose microfibril orientation in terms of director angle and anisotropy magnitude. Using this approach we detected differences between wild type rice plants and the rice brittle culm mutant, which shows a more disordered cellulose microfibril arrangement, and differences between different tissues of a wild type rice plant. This novel non-invasive Raman imaging approach allows for quantitative assessment of cellulose fiber orientation in cell walls of herbaceous plants, an important advancement in cell wall characterization.

  17. Quantitative non-invasive intracellular imaging of Plasmodium falciparum infected human erythrocytes

    NASA Astrophysics Data System (ADS)

    Edward, Kert; Farahi, Faramarz

    2014-05-01

    Malaria is a virulent pathological condition which results in over a million annual deaths. The parasitic agent Plasmodium falciparum has been extensively studied in connection with this epidemic but much remains unknown about its development inside the red blood cell host. Optical and fluorescence imaging are among the two most common procedures for investigating infected erythrocytes but both require the introduction of exogenous contrast agents. In this letter, we present a procedure for the non-invasive in situ imaging of malaria infected red blood cells. The procedure is based on the utilization of simultaneously acquired quantitative phase and independent topography data to extract intracellular information. Our method allows for the identification of the developmental stages of the parasite and facilitates in situ analysis of the morphological changes associated with the progression of this disease. This information may assist in the development of efficacious treatment therapies for this condition.

  18. Patient-specific volume conductor modeling for non-invasive imaging of cardiac electrophysiology.

    PubMed

    Pfeifer, B; Hanser, F; Seger, M; Fischer, G; Modre-Osprian, R; Tilg, B

    2008-01-01

    We propose a general workflow to numerically estimate the spread of electrical excitation in the patients' hearts. To this end, a semi-automatic segmentation pipeline for extracting the volume conductor model of structurally normal hearts is presented. The cardiac electrical source imaging technique aims to provide information about the spread of electrical excitation in order to assist the cardiologist in developing strategies for the treatment of cardiac arrhythmias. The volume conductor models of eight patients were extracted from cine-gated short-axis magnetic resonance imaging (MRI) data. The non-invasive estimation of electrical excitation was compared with the CARTO maps. The development of a volume conductor modeling pipeline for constructing a patient-specific volume conductor model in a fast and accurate way is one essential step to make the technique clinically applicable.

  19. Long Term Non-Invasive Imaging of Embryonic Stem Cells Using Reporter Genes

    PubMed Central

    Sun, Ning; Lee, Andrew; Wu, Joseph C.

    2013-01-01

    Development of non-invasive and accurate methods to track cell fate following delivery will greatly expedite transition of embryonic stem (ES) cell therapy to the clinic. Here we describe a protocol for the in vivo monitoring of stem cell survival, proliferation, and migration using reporter genes. We established stable ES cell lines constitutively expressing double fusion (DF; enhanced green fluorescent protein and firefly luciferase) or triple fusion (TF; monomeric red fluorescent protein, firefly luciferase, and herpes simplex virus thymidine kinase) reporter genes using lentiviral transduction. We used fluorescence activated cell sorting to purify these populations in vitro, bioluminescence imaging and positron emission tomography imaging to track them in vivo, and fluorescence immunostaining to confirm the results ex vivo. Unlike other methods of cell tracking such as iron particle and radionuclide labeling, reporter genes are inherited genetically and can be used to monitor cell proliferation and survival for the lifetime of transplanted cells and their progeny. PMID:19617890

  20. MO-E-BRD-01: Is Non-Invasive Image-Guided Breast Brachytherapy Good?

    SciTech Connect

    Hiatt, J.

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  1. Optimal Non-Invasive Fault Classification Model for Packaged Ceramic Tile Quality Monitoring Using MMW Imaging

    NASA Astrophysics Data System (ADS)

    Agarwal, Smriti; Singh, Dharmendra

    2016-04-01

    Millimeter wave (MMW) frequency has emerged as an efficient tool for different stand-off imaging applications. In this paper, we have dealt with a novel MMW imaging application, i.e., non-invasive packaged goods quality estimation for industrial quality monitoring applications. An active MMW imaging radar operating at 60 GHz has been ingeniously designed for concealed fault estimation. Ceramic tiles covered with commonly used packaging cardboard were used as concealed targets for undercover fault classification. A comparison of computer vision-based state-of-the-art feature extraction techniques, viz, discrete Fourier transform (DFT), wavelet transform (WT), principal component analysis (PCA), gray level co-occurrence texture (GLCM), and histogram of oriented gradient (HOG) has been done with respect to their efficient and differentiable feature vector generation capability for undercover target fault classification. An extensive number of experiments were performed with different ceramic tile fault configurations, viz., vertical crack, horizontal crack, random crack, diagonal crack along with the non-faulty tiles. Further, an independent algorithm validation was done demonstrating classification accuracy: 80, 86.67, 73.33, and 93.33 % for DFT, WT, PCA, GLCM, and HOG feature-based artificial neural network (ANN) classifier models, respectively. Classification results show good capability for HOG feature extraction technique towards non-destructive quality inspection with appreciably low false alarm as compared to other techniques. Thereby, a robust and optimal image feature-based neural network classification model has been proposed for non-invasive, automatic fault monitoring for a financially and commercially competent industrial growth.

  2. Non-invasive imaging of neuroanatomical structures and neural activation with high-resolution MRI.

    PubMed

    Herberholz, Jens; Mishra, Subrata H; Uma, Divya; Germann, Markus W; Edwards, Donald H; Potter, Kimberlee

    2011-01-01

    Several years ago, manganese-enhanced magnetic resonance imaging (MEMRI) was introduced as a new powerful tool to image active brain areas and to identify neural connections in living, non-human animals. Primarily restricted to studies in rodents and later adapted for bird species, MEMRI has recently been discovered as a useful technique for neuroimaging of invertebrate animals. Using crayfish as a model system, we highlight the advantages of MEMRI over conventional techniques for imaging of small nervous systems. MEMRI can be applied to image invertebrate nervous systems at relatively high spatial resolution, and permits identification of stimulus-evoked neural activation non-invasively. Since the selection of specific imaging parameters is critical for successful in vivo micro-imaging, we present an overview of different experimental conditions that are best suited for invertebrates. We also compare the effects of hardware and software specifications on image quality, and provide detailed descriptions of the steps necessary to prepare animals for successful imaging sessions. Careful consideration of hardware, software, experiments, and specimen preparation will promote a better understanding of this novel technique and facilitate future MEMRI studies in other laboratories.

  3. A field test study of our non-invasive thermal image analyzer for deceptive detection

    NASA Astrophysics Data System (ADS)

    Sumriddetchkajorn, Sarun; Somboonkaew, Armote; Sodsong, Tawee; Promduang, Itthipol; Sumriddetchkajorn, Niti

    2007-07-01

    We have developed a non-invasive thermal image analyzer for deceptive detection (TAD2) where the far-infrared data around the periorbital and nostril areas are simultaneously analyzed. Measured change in maximum skin temperature around two periorbital regions is converted to a relative blood flow velocity. A respiration pattern is also simultaneously determined via the ratio of the measured maximum and minimum temperatures in the nostril area. In addition, our TAD2 employs a simple normalized cross correlation scheme to independently track locations of the two periorbital and nostril areas. Our field case study from 7 subjects in two real crime scenes and with the use of our baseline classification criteria shows two-fold improvement in classification rate compared to our analysis using either the periorbital or nostril area alone.

  4. Thermal Imaging to Study Stress Non-invasively in Unrestrained Birds

    PubMed Central

    Jerem, Paul; Herborn, Katherine; McCafferty, Dominic; McKeegan, Dorothy; Nager, Ruedi

    2015-01-01

    Stress, a central concept in biology, describes a suite of emergency responses to challenges. Among other responses, stress leads to a change in blood flow that results in a net influx of blood to key organs and an increase in core temperature. This stress-induced hyperthermia is used to assess stress. However, measuring core temperature is invasive. As blood flow is redirected to the core, the periphery of the body can cool. This paper describes a protocol where peripheral body temperature is measured non-invasively in wild blue tits (Cyanistes caeruleus) using infrared thermography. In the field we created a set-up bringing the birds to an ideal position in front of the camera by using a baited box. The camera takes a short thermal video recording of the undisturbed bird before applying a mild stressor (closing the box and therefore capturing the bird), and the bird’s response to being trapped is recorded. The bare skin of the eye-region is the warmest area in the image. This allows an automated extraction of the maximum eye-region temperature from each image frame, followed by further steps of manual data filtering removing the most common sources of errors (motion blur, blinking). This protocol provides a time series of eye-region temperature with a fine temporal resolution that allows us to study the dynamics of the stress response non-invasively. Further work needs to demonstrate the usefulness of the method to assess stress, for instance to investigate whether eye-region temperature response is proportional to the strength of the stressor. If this can be confirmed, it will provide a valuable alternative method of stress assessment in animals and will be useful to a wide range of researchers from ecologists, conservation biologists, physiologists to animal welfare researchers. PMID:26575985

  5. A novel method for fast imaging of brain function, non-invasively, with light

    NASA Astrophysics Data System (ADS)

    Chance, Britton; Anday, Endla; Nioka, Shoko; Zhou, Shuoming; Hong, Long; Worden, Katherine; Li, C.; Murray, T.; Ovetsky, Y.; Pidikiti, D.; Thomas, R.

    1998-05-01

    Imaging of the human body by any non-invasive technique has been an appropriate goal of physics and medicine, and great success has been obtained with both Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) in brain imaging. Non-imaging responses to functional activation using near infrared spectroscopy of brain (fNIR) obtained in 1993 (Chance, et al. [1]) and in 1994 (Tamura, et al. [2]) are now complemented with images of pre-frontal and parietal stimulation in adults and pre-term neonates in this communication (see also [3]). Prior studies used continuous [4], pulsed [3] or modulated [5] light. The amplitude and phase cancellation of optical patterns as demonstrated for single source detector pairs affords remarkable sensitivity of small object detection in model systems [6]. The methods have now been elaborated with multiple source detector combinations (nine sources, four detectors). Using simple back projection algorithms it is now possible to image sensorimotor and cognitive activation of adult and pre- and full-term neonate human brain function in times < 30 sec and with two dimensional resolutions of < 1 cm in two dimensional displays. The method can be used in evaluation of adult and neonatal cerebral dysfunction in a simple, portable and affordable method that does not require immobilization, as contrasted to MRI and PET.

  6. Using Non-Invasive Multi-Spectral Imaging to Quantitatively Assess Tissue Vasculature

    SciTech Connect

    Vogel, A; Chernomordik, V; Riley, J; Hassan, M; Amyot, F; Dasgeb, B; Demos, S G; Pursley, R; Little, R; Yarchoan, R; Tao, Y; Gandjbakhche, A H

    2007-10-04

    This research describes a non-invasive, non-contact method used to quantitatively analyze the functional characteristics of tissue. Multi-spectral images collected at several near-infrared wavelengths are input into a mathematical optical skin model that considers the contributions from different analytes in the epidermis and dermis skin layers. Through a reconstruction algorithm, we can quantify the percent of blood in a given area of tissue and the fraction of that blood that is oxygenated. Imaging normal tissue confirms previously reported values for the percent of blood in tissue and the percent of blood that is oxygenated in tissue and surrounding vasculature, for the normal state and when ischemia is induced. This methodology has been applied to assess vascular Kaposi's sarcoma lesions and the surrounding tissue before and during experimental therapies. The multi-spectral imaging technique has been combined with laser Doppler imaging to gain additional information. Results indicate that these techniques are able to provide quantitative and functional information about tissue changes during experimental drug therapy and investigate progression of disease before changes are visibly apparent, suggesting a potential for them to be used as complementary imaging techniques to clinical assessment.

  7. Visualization and quantification of simian immunodeficiency virus-infected cells using non-invasive molecular imaging

    PubMed Central

    Song, Jiasheng; Cai, Zhengxin; White, Alexander G.; Jin, Tao; Wang, Xiaolei; Kadayakkara, Deepak; Anderson, Carolyn J.; Ambrose, Zandrea

    2015-01-01

    In vivo imaging can provide real-time information and three-dimensional (3D) non-invasive images of deep tissues and organs, including the brain, whilst allowing longitudinal observation of the same animals, thus eliminating potential variation between subjects. Current in vivo imaging technologies, such as magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT) and bioluminescence imaging (BLI), can be used to pinpoint the spatial location of target cells, which is urgently needed for revealing human immunodeficiency virus (HIV) dissemination in real-time and HIV-1 reservoirs during suppressive antiretroviral therapy (ART). To demonstrate that in vivo imaging can be used to visualize and quantify simian immunodeficiency virus (SIV)-transduced cells, we genetically engineered SIV to carry different imaging reporters. Based on the expression of the reporter genes, we could visualize and quantify the SIV-transduced cells via vesicular stomatitis virus glycoprotein pseudotyping in a mouse model using BLI, PET-CT or MRI. We also engineered a chimeric EcoSIV for in vivo infection study. Our results demonstrated that BLI is sensitive enough to detect as few as five single cells transduced with virus, whilst PET-CT can provide 3D images of the spatial location of as few as 10 000 SIV-infected cells. We also demonstrated that MRI can provide images with high spatial resolution in a 3D anatomical context to distinguish a small population of SIV-transduced cells. The in vivo imaging platform described here can potentially serve as a powerful tool to visualize lentiviral infection, including when and where viraemia rebounds, and how reservoirs are formed and maintained during latency or suppressive ART. PMID:26297664

  8. Non-invasive Imaging of Idiopathic Pulmonary Fibrosis Using Cathepsin Protease Probes.

    PubMed

    Withana, Nimali P; Ma, Xiaowei; McGuire, Helen M; Verdoes, Martijn; van der Linden, Wouter A; Ofori, Leslie O; Zhang, Ruiping; Li, Hao; Sanman, Laura E; Wei, Ke; Yao, Shaobo; Wu, Peilin; Li, Fang; Huang, Hui; Xu, Zuojun; Wolters, Paul J; Rosen, Glenn D; Collard, Harold R; Zhu, Zhaohui; Cheng, Zhen; Bogyo, Matthew

    2016-01-22

    Idiopathic pulmonary fibrosis (IPF) is a lethal, chronic, progressive disease characterized by formation of scar tissue within the lungs. Because it is a disease of unknown etiology, it is difficult to diagnose, to predict disease course and to devise treatment strategies. Recent evidence suggests that activated macrophages play key roles in the pathology of IPF. Therefore, imaging probes that specifically recognize these pools of activated immune cells could provide valuable information about how these cells contribute to the pathobiology of the disease. Here we demonstrate that cysteine cathepsin-targeted imaging probes can be used to monitor the contribution of macrophages to fibrotic disease progression in the bleomycin-induced murine model of pulmonary fibrosis. Furthermore, we show that the probes highlight regions of macrophage involvement in fibrosis in human biopsy tissues from IPF patients. Finally, we present first-in-human results demonstrating non-invasive imaging of active cathepsins in fibrotic lesions of patients with IPF. Together, our findings validate small molecule cysteine cathepsin probes for clinical PET imaging and suggest that they have the potential to be used to generate mechanistically-informative molecular information regarding cellular drivers of IPF disease severity and progression.

  9. Non-invasive imaging of oxygen extraction fraction in adults with sickle cell anaemia.

    PubMed

    Jordan, Lori C; Gindville, Melissa C; Scott, Allison O; Juttukonda, Meher R; Strother, Megan K; Kassim, Adetola A; Chen, Sheau-Chiann; Lu, Hanzhang; Pruthi, Sumit; Shyr, Yu; Donahue, Manus J

    2016-03-01

    Sickle cell anaemia is a monogenetic disorder with a high incidence of stroke. While stroke screening procedures exist for children with sickle cell anaemia, no accepted screening procedures exist for assessing stroke risk in adults. The purpose of this study is to use novel magnetic resonance imaging methods to evaluate physiological relationships between oxygen extraction fraction, cerebral blood flow, and clinical markers of cerebrovascular impairment in adults with sickle cell anaemia. The specific goal is to determine to what extent elevated oxygen extraction fraction may be uniquely present in patients with higher levels of clinical impairment and therefore may represent a candidate biomarker of stroke risk. Neurological evaluation, structural imaging, and the non-invasive T2-relaxation-under-spin-tagging magnetic resonance imaging method were applied in sickle cell anaemia (n = 34) and healthy race-matched control (n = 11) volunteers without sickle cell trait to assess whole-brain oxygen extraction fraction, cerebral blood flow, degree of vasculopathy, severity of anaemia, and presence of prior infarct; findings were interpreted in the context of physiological models. Cerebral blood flow and oxygen extraction fraction were elevated (P < 0.05) in participants with sickle cell anaemia (n = 27) not receiving monthly blood transfusions (interquartile range cerebral blood flow = 46.2-56.8 ml/100 g/min; oxygen extraction fraction = 0.39-0.50) relative to controls (interquartile range cerebral blood flow = 40.8-46.3 ml/100 g/min; oxygen extraction fraction = 0.33-0.38). Oxygen extraction fraction (P < 0.0001) but not cerebral blood flow was increased in participants with higher levels of clinical impairment. These data provide support for T2-relaxation-under-spin-tagging being able to quickly and non-invasively detect elevated oxygen extraction fraction in individuals with sickle cell anaemia with higher levels of clinical impairment. Our results support the

  10. Multifunctional single beam acoustic tweezer for non-invasive cell/organism manipulation and tissue imaging

    PubMed Central

    Lam, Kwok Ho; Li, Ying; Li, Yang; Lim, Hae Gyun; Zhou, Qifa; Shung, Koping Kirk

    2016-01-01

    Non-contact precise manipulation of single microparticles, cells, and organisms has attracted considerable interest in biophysics and biomedical engineering. Similar to optical tweezers, acoustic tweezers have been proposed to be capable of manipulating microparticles and even cells. Although there have been concerted efforts to develop tools for non-contact manipulation, no alternative to complex, unifunctional tweezer has yet been found. Here we report a simple, low-cost, multifunctional single beam acoustic tweezer (SBAT) that is capable of manipulating an individual micrometer scale non-spherical cell at Rayleigh regime and even a single millimeter scale organism at Mie regime, and imaging tissue as well. We experimentally demonstrate that the SBAT with an ultralow f-number (f# = focal length/aperture size) could manipulate an individual red blood cell and a single 1.6 mm-diameter fertilized Zebrafish egg, respectively. Besides, in vitro rat aorta images were collected successfully at dynamic foci in which the lumen and the outer surface of the aorta could be clearly seen. With the ultralow f-number, the SBAT offers the combination of large acoustic radiation force and narrow beam width, leading to strong trapping and high-resolution imaging capabilities. These attributes enable the feasibility of using a single acoustic device to perform non-invasive multi-functions simultaneously for biomedical and biophysical applications. PMID:27874052

  11. Multifunctional single beam acoustic tweezer for non-invasive cell/organism manipulation and tissue imaging

    NASA Astrophysics Data System (ADS)

    Lam, Kwok Ho; Li, Ying; Li, Yang; Lim, Hae Gyun; Zhou, Qifa; Shung, Koping Kirk

    2016-11-01

    Non-contact precise manipulation of single microparticles, cells, and organisms has attracted considerable interest in biophysics and biomedical engineering. Similar to optical tweezers, acoustic tweezers have been proposed to be capable of manipulating microparticles and even cells. Although there have been concerted efforts to develop tools for non-contact manipulation, no alternative to complex, unifunctional tweezer has yet been found. Here we report a simple, low-cost, multifunctional single beam acoustic tweezer (SBAT) that is capable of manipulating an individual micrometer scale non-spherical cell at Rayleigh regime and even a single millimeter scale organism at Mie regime, and imaging tissue as well. We experimentally demonstrate that the SBAT with an ultralow f-number (f# = focal length/aperture size) could manipulate an individual red blood cell and a single 1.6 mm-diameter fertilized Zebrafish egg, respectively. Besides, in vitro rat aorta images were collected successfully at dynamic foci in which the lumen and the outer surface of the aorta could be clearly seen. With the ultralow f-number, the SBAT offers the combination of large acoustic radiation force and narrow beam width, leading to strong trapping and high-resolution imaging capabilities. These attributes enable the feasibility of using a single acoustic device to perform non-invasive multi-functions simultaneously for biomedical and biophysical applications.

  12. Non-invasive stratification of postinfarction rats based on degree of cardiac dysfunction using magnetic resonance imaging and echocardiography.

    PubMed

    Aronsen, Jan Magnus; Espe, Emil Knut Stenersen; Skårdal, Kristine; Hasic, Almira; Zhang, Lili; Sjaastad, Ivar

    2017-02-10

    The myocardial infarction (MI) rat model plays a crucial role in modern cardiovascular research, but the inherent heterogeneity of this model represents a challenge. We sought to identify subgroups among the post-MI rats, and establish simple non-invasive stratification protocols for such subgroups. Six weeks after induction of MI, 49 rats underwent non-invasive examinations using magnetic resonance imaging (MRI) and echocardiography. 12 sham-operated rats served as controls. Increased end-diastolic left ventricular (LV) pressure and lung weight served as indicators for congestive heart failure (CHF). A clustering algorithm using thirteen non-invasive and invasive parameters was used to identify distinct groups among the animals. The cluster analysis revealed four distinct post-MI phenotypes; two without congestion but with different degree of LV dilatation, and two with different degree of congestion and right ventricular (RV) affection. Among the MRI parameters, RV mass emerged as robust non-invasive marker of CHF with 100% specificity/sensitivity. Moreover, LV infarct size and RV ejection fraction further predicted subgroup among the non-CHF and CHF rats with excellent specificity/sensitivity. Of the echocardiography parameters, left atrial diameter predicted CHF. Moreover, MRI-derived LV end-diastolic diameter predicted the subgroups among the non-CHF rats. We propose two simple non-invasive schemes to stratify post-MI rats, based on the degree of heart failure; one for MRI and one for echocardiography.

  13. A method for non-invasive full-field imaging and quantification of chemical species.

    PubMed

    Shkolnikov, Viktor; Santiago, Juan G

    2013-04-21

    We present a novel method for full-field scalar visualization and quantification of species concentration fields. We term this method species-altered fluorescence imaging (SAFI). The method employs electrically neutral fluorescent dyes whose quantum yields are selectively quenched or enhanced by species of interest. SAFI enables simultaneous imaging of material interfaces and provides non-invasive, scalar-field quantitation of two-dimensional species concentration fields. We describe criteria for choosing SAFI dyes and tabulate 35 promising SAFI dyes and their relevant properties. Next, we describe species concentration quantification with SAFI via Stern-Volmer quenching and discuss the sensitivity and resolution of our method. We demonstrate this method with two dyes, 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ) and 10-(3-sulfopropyl)acridinium betaine (SAB). We demonstrate our method in full-field visualization of several challenging electrokinetic flows: isotachophoresis (ITP) in both cationic and anionic modes, and in a convective electrokinetic instability (EKI) flow. Through these experiments we collectively quantify ion concentration shock velocities, simultaneously measure concentrations of five species, and quantify the development of an unsteady, chaotic, 2D flow.

  14. Image-guided ultrasound phased arrays are a disruptive technology for non-invasive therapy

    NASA Astrophysics Data System (ADS)

    Hynynen, Kullervo; Jones, Ryan M.

    2016-09-01

    Focused ultrasound offers a non-invasive way of depositing acoustic energy deep into the body, which can be harnessed for a broad spectrum of therapeutic purposes, including tissue ablation, the targeting of therapeutic agents, and stem cell delivery. Phased array transducers enable electronic control over the beam geometry and direction, and can be tailored to provide optimal energy deposition patterns for a given therapeutic application. Their use in combination with modern medical imaging for therapy guidance allows precise targeting, online monitoring, and post-treatment evaluation of the ultrasound-mediated bioeffects. In the past there have been some technical obstacles hindering the construction of large aperture, high-power, densely-populated phased arrays and, as a result, they have not been fully exploited for therapy delivery to date. However, recent research has made the construction of such arrays feasible, and it is expected that their continued development will both greatly improve the safety and efficacy of existing ultrasound therapies as well as enable treatments that are not currently possible with existing technology. This review will summarize the basic principles, current statures, and future potential of image-guided ultrasound phased arrays for therapy.

  15. Non-invasive molecular profiling of cancer using photoacoustic imaging of functionalized gold nanorods

    NASA Astrophysics Data System (ADS)

    Shah, Anant J.; Alles, Erwin J.; Box, Carol; Eccles, Suzanne A.; Robinson, Simon P.; deSouza, Nandita; Bamber, Jeffrey C.

    2014-03-01

    Although molecularly targeted cancer therapies have shown great promise, it is now evident that responses are dependent upon the molecular genetic context. Spatial and temporal tumour heterogeneity renders biopsy of solid tumours unsuitable for determining the genetic profile of the disease, making adaptation of appropriate therapy difficult. We have utilized the tunable optical absorption characteristic of gold nanorods to assess the potential of photoacoustics for non-invasive multiplexed molecular imaging. Gold nanorods with resonance peaks at 700nm and 900nm were functionalised with in-house antibodies ICR55 and ICR62, targeted to HER2 and EGFR transmembrane receptors, respectively. Three human squamous carcinoma cell lines (LICR-LON-HN4 expressing high HER2 and low EGFR, LICR-LON-HN3 expressing intermediate levels of HER2 and EGFR and A431 expressing high EGFR and low HER2) were incubated with the targeted nanorods for 24 hours. Cells were then incorporated as simulated tumours in tissue-like phantoms composed of 7.5% gelatin containing 0.5% Intralipid® for optical scattering and imaged at a depth of 2.5 cm, using a new clinical in-house multi-spectral photoacoustic imaging system. Images were obtained from the cell inclusions for wavelengths ranging from 710 to 950 nm at 40 nm intervals, and the mean amplitude of the photoacoustic image was computed for each wavelength, to determine their relative receptor expression levels. The molecular profile of the cells obtained using multi-wavelength photoacoustics had substantial similarity to that obtained using flow cytometry. These preliminary results confirm selective uptake of the functionalised nanorods, which reflects the cellular expression of therapeutically important oncoproteins, and give an indication of the potential of photoacoustics for multiplexed molecular profiling.

  16. 3D fluoroscopic image estimation using patient-specific 4DCBCT-based motion models

    NASA Astrophysics Data System (ADS)

    Dhou, S.; Hurwitz, M.; Mishra, P.; Cai, W.; Rottmann, J.; Li, R.; Williams, C.; Wagar, M.; Berbeco, R.; Ionascu, D.; Lewis, J. H.

    2015-05-01

    3D fluoroscopic images represent volumetric patient anatomy during treatment with high spatial and temporal resolution. 3D fluoroscopic images estimated using motion models built using 4DCT images, taken days or weeks prior to treatment, do not reliably represent patient anatomy during treatment. In this study we developed and performed initial evaluation of techniques to develop patient-specific motion models from 4D cone-beam CT (4DCBCT) images, taken immediately before treatment, and used these models to estimate 3D fluoroscopic images based on 2D kV projections captured during treatment. We evaluate the accuracy of 3D fluoroscopic images by comparison to ground truth digital and physical phantom images. The performance of 4DCBCT-based and 4DCT-based motion models are compared in simulated clinical situations representing tumor baseline shift or initial patient positioning errors. The results of this study demonstrate the ability for 4DCBCT imaging to generate motion models that can account for changes that cannot be accounted for with 4DCT-based motion models. When simulating tumor baseline shift and patient positioning errors of up to 5 mm, the average tumor localization error and the 95th percentile error in six datasets were 1.20 and 2.2 mm, respectively, for 4DCBCT-based motion models. 4DCT-based motion models applied to the same six datasets resulted in average tumor localization error and the 95th percentile error of 4.18 and 5.4 mm, respectively. Analysis of voxel-wise intensity differences was also conducted for all experiments. In summary, this study demonstrates the feasibility of 4DCBCT-based 3D fluoroscopic image generation in digital and physical phantoms and shows the potential advantage of 4DCBCT-based 3D fluoroscopic image estimation when there are changes in anatomy between the time of 4DCT imaging and the time of treatment delivery.

  17. 3D fluoroscopic image estimation using patient-specific 4DCBCT-based motion models

    PubMed Central

    Dhou, Salam; Hurwitz, Martina; Mishra, Pankaj; Cai, Weixing; Rottmann, Joerg; Li, Ruijiang; Williams, Christopher; Wagar, Matthew; Berbeco, Ross; Ionascu, Dan; Lewis, John H.

    2015-01-01

    3D fluoroscopic images represent volumetric patient anatomy during treatment with high spatial and temporal resolution. 3D fluoroscopic images estimated using motion models built using 4DCT images, taken days or weeks prior to treatment, do not reliably represent patient anatomy during treatment. In this study we develop and perform initial evaluation of techniques to develop patient-specific motion models from 4D cone-beam CT (4DCBCT) images, taken immediately before treatment, and use these models to estimate 3D fluoroscopic images based on 2D kV projections captured during treatment. We evaluate the accuracy of 3D fluoroscopic images by comparing to ground truth digital and physical phantom images. The performance of 4DCBCT- and 4DCT- based motion models are compared in simulated clinical situations representing tumor baseline shift or initial patient positioning errors. The results of this study demonstrate the ability for 4DCBCT imaging to generate motion models that can account for changes that cannot be accounted for with 4DCT-based motion models. When simulating tumor baseline shift and patient positioning errors of up to 5 mm, the average tumor localization error and the 95th percentile error in six datasets were 1.20 and 2.2 mm, respectively, for 4DCBCT-based motion models. 4DCT-based motion models applied to the same six datasets resulted in average tumor localization error and the 95th percentile error of 4.18 and 5.4 mm, respectively. Analysis of voxel-wise intensity differences was also conducted for all experiments. In summary, this study demonstrates the feasibility of 4DCBCT-based 3D fluoroscopic image generation in digital and physical phantoms, and shows the potential advantage of 4DCBCT-based 3D fluoroscopic image estimation when there are changes in anatomy between the time of 4DCT imaging and the time of treatment delivery. PMID:25905722

  18. Combined Neutron and X-ray Imaging for Non-invasive Investigations of Cultural Heritage Objects

    NASA Astrophysics Data System (ADS)

    Mannes, D.; Schmid, F.; Frey, J.; Schmidt-Ott, K.; Lehmann, E.

    The combined utilization of neutron and X-ray imaging for non-invasive investigations of cultural heritage objects is demonstrated on the example of a short sword found a few years ago in lake Zug, Switzerland. After conservation treatments carried out at the Swiss National Museum the sword was examined at the Paul Scherrer Institut (PSI), Villigen (CH), by means of neutron and X-ray computer tomography (CT). The two types of radiation show different interaction behavior with matter, which makes the two methods complementary. While X-rays show a strong correlation of the attenuation with the atomic number, neutrons demonstrate a high sensitivity for some light elements, such as Hydrogen and thus organic material, while some heavy elements (such as Lead) show high penetrability. The examined object is a composite of metal and organic material, which makes it an ideal example to show the complementarity of the two methods as it features materials, which are rather transparent for one type of radiation, while yielding at the same time high contrast for the other. Only the combination of the two methods made an exhaustive examination of the object possible and allowed to rebuild an accurate replica of the sword.

  19. Analysis of progenitor cell-scaffold combinations by in vivo non-invasive photonic imaging.

    PubMed

    Román, Irene; Vilalta, Marta; Rodriguez, Julio; Matthies, Annette M; Srouji, Samer; Livne, Erella; Hubbell, Jeffrey A; Rubio, Nuria; Blanco, Jerónimo

    2007-06-01

    Recent developments in stem cell research have promoted a flourishing of new biomaterials and scaffolds for tissue repair. However, there is a scarcity of procedures to monitor the performance of scaffold-stem cell combinations implanted in live animals, avoiding the inherent artefacts associated with in vitro assay conditions. We report the implementation of a procedure based on the use of the luciferase gene as a cell proliferation tracer to monitor, by in vivo non-invasive imaging, the performance of stem cell-biomaterial combinations used for tissue regeneration. In a model system using immunodepressed mice we show preference of a mouse embryonic mesenchymal cell line (C3H/10T1/2) for specific implantation sites and biomaterials during a prolonged in vivo growth period (3 months). Moreover, we analyzed the safety of implanted cells using a sensitive luminometric procedure and showed that the implanted cells did not spread to other organs. Our results demonstrate the utility of this simple and resource-saving procedure in the development and screening of biomaterials for tissue engineering.

  20. Imaging iron in skin and liver: Non-invasive tools for hemochromatosis therapy

    NASA Astrophysics Data System (ADS)

    Pinheiro, T.; Fleming, R.; Gonçalves, A.; Neres, M.; Alves, L. C.; Silva, J. N.; Filipe, P.; Silva, R.

    2009-06-01

    Hemochromatosis is a hereditary disease that causes an inappropriate intestinal absorption of Fe resulting in its accumulation in multiple organs, such as liver, heart and skin. Fe metabolism indicators in the circulation do not provide reliable indication of organ overload as they can be influenced by other clinical conditions. Assessing metabolism organs such as liver requires invasive procedures which is not adequate to patient's serial observations. Our aim was establishing cross sectional and longitudinal information on the amount of Fe that deposited in skin and liver during a life period, how iron is cleared out by therapy intervention and study the relationship of these changes between the two organs using non-invasive methods. Results on skin Fe deposition were evaluated by nuclear microscopy techniques and liver Fe concentrations determined by quantitative magnetic resonance imaging. Skin and liver Fe concentrations were correlated. Though Fe deposits in the two organs were differently associated with blood Fe metabolism conventional markers. Fe serial variations in skin and liver highlighted the value of assessing Fe organ deposits for estimating hemochromatosis evolution and therapy efficacy.

  1. Non-invasive imaging of transgenic GFP expression in neonatal mouse brain

    NASA Astrophysics Data System (ADS)

    Ho, Gideon; Zhang, Chunyan; Zhuo, Lang

    2007-02-01

    Glial fibrillary acidic protein (GFAP) is a traditional biomarker for astrocytes of the central nervous system. In this study, non-invasive in vivo imaging of GFAP-GFP (green fluorescent protein) expression in the brain of neonatal transgenic mice is used as a novel method to investigate the relationship between the expression of the transgene at 0, 2, 4, 6 and 8 hr post-treatment in mice subjected to a single administration of 12 mg/kg of neurotoxin 1-methyl-4(2'-methylphenyl)-1,2,3,6-tetrahydropyridine (2'-CH 3-MPTP). The GFP elevation was found to peak at 6 hr and lasted to at least 8 hr after the toxin treatment. Histological examination of fixed brain sections using immunohistochemistry (IHC) shows an increase in GFP and GFAP signal from the substantia nigra pars compacta (SNpc) and the hippocampus. The results have provided quantitative fluorescence and qualitative histological evidence for the activation of the GFAP-GFP transgene in astrocytes following neurotoxin 2'-CH 3-MPTP administration, suggesting that the model described here could be used to study neuronal degeneration such as Parkinson's disease and in general, developmental neurotoxicity in live animals.

  2. Apoptosis imaging for monitoring DR5 antibody accumulation and pharmacodynamics in brain tumors non-invasively

    PubMed Central

    Weber, Thomas G.; Osl, Franz; Renner, Anja; Pöschinger, Thomas; Galbán, Stefanie; Rehemtulla, Alnawaz; Scheuer, Werner

    2014-01-01

    High grade gliomas often possess an impaired blood-brain barrier (BBB) which allows delivery of large molecules to brain tumors. However, achieving optimal drug concentrations in brain tumors remains a significant hurdle for treating patients successfully. Thus, detailed investigations of drug activities in gliomas are needed. To investigate BBB penetration, pharmacodynamics and tumor retention kinetics, we studied an agonistic DR5 antibody in a brain tumor xenograft model to investigate a non-invasive imaging method for longitudinal monitoring of apoptosis induction by this antibody. Brain tumors were induced by intracranial (i.c.) implantation of a luciferase-expressing tumor cell line as a reporter. To quantify accumulation of anti-DR5 in brain tumors, we generated a dose response curve for apoptosis induction after i.c. delivery of fluorescence-labeled anti-DR5 at different dosages. Assuming 100% drug delivery after i.c. application, the amount of accumulated antibody after i.v. application was calculated relative to its apoptosis induction. We found that up to 0.20–0.97% of antibody delivered i.v. reached the brain tumor, but that apoptosis induction declined quickly within 24 hours. These results were confirmed by 3D fluorescence microscopy of antibody accumulation in explanted brains. Nonetheless, significant antitumor efficacy was documented after anti-DR5 delivery. We further demonstrated that antibody crossing the BBB was facilitated its impairment in brain tumors. These imaging methods enable the quantification of antibody accumulation and pharmacodynamics in brain tumors, offering a holistic approach for assessment of CNS targeting drugs. PMID:24509903

  3. 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

  4. Non-invasive and non-destructive characterization of tissue engineered constructs using ultrasound imaging technologies: a review

    PubMed Central

    Kim, Kang; Wagner, William R.

    2015-01-01

    With the rapid expansion of biomaterial development and coupled efforts to translate such advances toward the clinic, non-invasive and non-destructive imaging tools to evaluate implants in situ in a timely manner are critically needed. The required multilevel information is comprehensive, including structural, mechanical, and biological changes such as scaffold degradation, mechanical strength, cell infiltration, extracellular matrix formation and vascularization to name a few. With its inherent advantages of non-invasiveness and non-destructiveness, ultrasound imaging can be an ideal tool for both preclinical and clinical uses. In this review, currently available ultrasound imaging technologies that have been applied in vitro and in vivo for tissue engineering and regenerative medicine are discussed and some new emerging ultrasound technologies and multi-modality approaches utilizing ultrasound are introduced. PMID:26518412

  5. Non-invasive and Non-destructive Characterization of Tissue Engineered Constructs Using Ultrasound Imaging Technologies: A Review.

    PubMed

    Kim, Kang; Wagner, William R

    2016-03-01

    With the rapid expansion of biomaterial development and coupled efforts to translate such advances toward the clinic, non-invasive and non-destructive imaging tools to evaluate implants in situ in a timely manner are critically needed. The required multi-level information is comprehensive, including structural, mechanical, and biological changes such as scaffold degradation, mechanical strength, cell infiltration, extracellular matrix formation and vascularization to name a few. With its inherent advantages of non-invasiveness and non-destructiveness, ultrasound imaging can be an ideal tool for both preclinical and clinical uses. In this review, currently available ultrasound imaging technologies that have been applied in vitro and in vivo for tissue engineering and regenerative medicine are discussed and some new emerging ultrasound technologies and multi-modality approaches utilizing ultrasound are introduced.

  6. Imaging the Efficacy of Anti-Inflammatory Liposomes in a Rabbit Model of Atherosclerosis by Non-Invasive Imaging

    PubMed Central

    Lobatto, Mark E.; Calcagno, Claudia; Metselaar, Josbert M.; Storm, Gert; Stroes, Erik S. G.; Fayad, Zahi A.; Mulder, Willem J. M.

    2013-01-01

    Nanomedicine can provide a potent alternative to current therapeutic strategies for atherosclerosis. For example, the encapsulation of anti-inflammatory drugs into liposomes improves their pharmacokinetics and biodistribution, thereby enhancing bioavailability to atherosclerotic plaques and improving therapeutic efficacy. The evaluation of this type of experimental therapeutics can greatly benefit from in vivo evaluation to assess biological changes, which can be performed by non-invasive imaging techniques, such as 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Here, we will illustrate the methods for inducing atherosclerosis in a rabbit model, the production of anti-inflammatory liposomes and monitoring of therapeutic efficacy of experimental therapeutics with the above-mentioned imaging techniques. PMID:22449928

  7. Imaging the efficacy of anti-inflammatory liposomes in a rabbit model of atherosclerosis by non-invasive imaging.

    PubMed

    Lobatto, Mark E; Calcagno, Claudia; Metselaar, Josbert M; Storm, Gert; Stroes, Erik S G; Fayad, Zahi A; Mulder, Willem J M

    2012-01-01

    Nanomedicine can provide a potent alternative to current therapeutic strategies for atherosclerosis. For example, the encapsulation of anti-inflammatory drugs into liposomes improves their pharmacokinetics and biodistribution, thereby enhancing bioavailability to atherosclerotic plaques and improving therapeutic efficacy. The evaluation of this type of experimental therapeutics can greatly benefit from in vivo evaluation to assess biological changes, which can be performed by non-invasive imaging techniques, such as ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Here, we will illustrate the methods for inducing atherosclerosis in a rabbit model, the production of anti-inflammatory liposomes and monitoring of therapeutic efficacy of experimental therapeutics with the above-mentioned imaging techniques.

  8. Application of quantum dot nanoparticles for potential non-invasive bio-imaging of mammalian spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various obstacles are encountered by mammalian spermatozoa during their journey through the female genital tract, and only few or none will reach the site of fertilization. Currently, there are limited technical approaches for non-invasive investigation of spermatozoa migration after insemination. A...

  9. Evaluation of biolistic gene transfer methods in vivo using non-invasive bioluminescent imaging techniques

    PubMed Central

    2011-01-01

    Background Gene therapy continues to hold great potential for treating many different types of disease and dysfunction. Safe and efficient techniques for gene transfer and expression in vivo are needed to enable gene therapeutic strategies to be effective in patients. Currently, the most commonly used methods employ replication-defective viral vectors for gene transfer, while physical gene transfer methods such as biolistic-mediated ("gene-gun") delivery to target tissues have not been as extensively explored. In the present study, we evaluated the efficacy of biolistic gene transfer techniques in vivo using non-invasive bioluminescent imaging (BLI) methods. Results Plasmid DNA carrying the firefly luciferase (LUC) reporter gene under the control of the human Cytomegalovirus (CMV) promoter/enhancer was transfected into mouse skin and liver using biolistic methods. The plasmids were coupled to gold microspheres (1 μm diameter) using different DNA Loading Ratios (DLRs), and "shot" into target tissues using a helium-driven gene gun. The optimal DLR was found to be in the range of 4-10. Bioluminescence was measured using an In Vivo Imaging System (IVIS-50) at various time-points following transfer. Biolistic gene transfer to mouse skin produced peak reporter gene expression one day after transfer. Expression remained detectable through four days, but declined to undetectable levels by six days following gene transfer. Maximum depth of tissue penetration following biolistic transfer to abdominal skin was 200-300 μm. Similarly, biolistic gene transfer to mouse liver in vivo also produced peak early expression followed by a decline over time. In contrast to skin, however, liver expression of the reporter gene was relatively stable 4-8 days post-biolistic gene transfer, and remained detectable for nearly two weeks. Conclusions The use of bioluminescence imaging techniques enabled efficient evaluation of reporter gene expression in vivo. Our results demonstrate that

  10. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1650...

  11. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1650...

  12. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1660...

  13. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1650...

  14. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1650...

  15. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1650...

  16. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1660...

  17. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1660...

  18. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1660...

  19. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1660...

  20. In vivo fibered confocal reflectance imaging: totally non-invasive morphological cellular imaging brought to the endoscopist

    NASA Astrophysics Data System (ADS)

    Osdoit, Anne; Genet, Magalie; Perchant, Aymeric; Loiseau, Sacha; Abrat, Benjamin; Lacombe, François

    2006-02-01

    This paper presents a novel fibered confocal reflectance microscopy system (FCRM) specifically designed for the medical observation of biological tissues in vivo and in situ, in real time, at the cellular level: the R-600. Reflectance imaging is based on the refraction index difference between biological components while confocal imaging allow to perform the optical sectioning slice in-depth inside the tissues. The R-600 is based on a proximal scanning system, coupled with a 7 mm diameter probe made of tens of thousands of flexible optical fibers allowing in situ imaging, associated with a dedicated software performing real-time control and image processing. The R-600 provides 12 frames per second at an optical imaging depth of 30 microns, with a high lateral resolution, 1 micron, an axial resolution of 2 microns in a field of view 160 microns in diameter. Thanks to the miniaturization of the optical probe, unprecedented accessibility is made possible in organs such as the cervix or the otolaryngological sphere, in a completely non-invasive fashion. The aim of FCRM is to perform optical biopsy. As a first step towards this goal, we present here results obtained in vivo and in real-time on a human mouth , assessing the ability of the R-600 to perform rapid morphologic examination. Subcellular structures such as nuclei and membranes can be clearly distinguished on the images. Further miniaturization opens perspectives for an integrated endoscope-compatible system with broad medical applications.

  1. Profiling neuronal ion channelopathies with non-invasive brain imaging and dynamic causal models: Case studies of single gene mutations

    PubMed Central

    Gilbert, Jessica R.; Symmonds, Mkael; Hanna, Michael G.; Dolan, Raymond J.; Friston, Karl J.; Moran, Rosalyn J.

    2016-01-01

    Clinical assessments of brain function rely upon visual inspection of electroencephalographic waveform abnormalities in tandem with functional magnetic resonance imaging. However, no current technology proffers in vivo assessments of activity at synapses, receptors and ion-channels, the basis of neuronal communication. Using dynamic causal modeling we compared electrophysiological responses from two patients with distinct monogenic ion channelopathies and a large cohort of healthy controls to demonstrate the feasibility of assaying synaptic-level channel communication non-invasively. Synaptic channel abnormality was identified in both patients (100% sensitivity) with assay specificity above 89%, furnishing estimates of neurotransmitter and voltage-gated ion throughput of sodium, calcium, chloride and potassium. This performance indicates a potential novel application as an adjunct for clinical assessments in neurological and psychiatric settings. More broadly, these findings indicate that biophysical models of synaptic channels can be estimated non-invasively, having important implications for advancing human neuroimaging to the level of non-invasive ion channel assays. PMID:26342528

  2. MR cone-beam CT fusion image overlay for fluoroscopically guided percutaneous biopsies in pediatric patients.

    PubMed

    Thakor, Avnesh S; Patel, Premal A; Gu, Richard; Rea, Vanessa; Amaral, Joao; Connolly, Bairbre L

    2016-03-01

    Lesions only visible on magnetic resonance (MR) imaging cannot easily be targeted for image-guided biopsy using ultrasound or X-rays but instead require MR guidance with MR-compatible needles and long procedure times (acquisition of multiple MR sequences). We developed an alternative method for performing these difficult biopsies in a standard interventional suite, by fusing MR with cone-beam CT images. The MR cone-beam CT fusion image is then used as an overlay to guide a biopsy needle to the target area under live fluoroscopic guidance. Advantages of this technique include (i) the ability for it to be performed in a conventional interventional suite, (ii) three-dimensional planning of the needle trajectory using cross-sectional imaging, (iii) real-time fluoroscopic guidance for needle trajectory correction and (iv) targeting within heterogeneous lesions based on MR signal characteristics to maximize the potential biopsy yield.

  3. Non-invasive imaging methods applied to neo- and paleontological cephalopod research

    NASA Astrophysics Data System (ADS)

    Hoffmann, R.; Schultz, J. A.; Schellhorn, R.; Rybacki, E.; Keupp, H.; Gerden, S. R.; Lemanis, R.; Zachow, S.

    2013-11-01

    Several non-invasive methods are common practice in natural sciences today. Here we present how they can be applied and contribute to current topics in cephalopod (paleo-) biology. Different methods will be compared in terms of time necessary to acquire the data, amount of data, accuracy/resolution, minimum-maximum size of objects that can be studied, of the degree of post-processing needed and availability. Main application of the methods is seen in morphometry and volumetry of cephalopod shells in order to improve our understanding of diversity and disparity, functional morphology and biology of extinct and extant cephalopods.

  4. Non-invasive near-infrared fluorescence imaging of the neutrophil response in a mouse model of transient cerebral ischaemia.

    PubMed

    Vaas, Markus; Enzmann, Gaby; Perinat, Therese; Siler, Ulrich; Reichenbach, Janine; Licha, Kai; Kipar, Anja; Rudin, Markus; Engelhardt, Britta; Klohs, Jan

    2016-10-27

    Near-infrared fluorescence (NIRF) imaging enables non-invasive monitoring of molecular and cellular processes in live animals. Here we demonstrate the suitability of NIRF imaging to investigate the neutrophil response in the brain after transient middle cerebral artery occlusion (tMCAO). We established procedures for ex vivo fluorescent labelling of neutrophils without affecting their activation status. Adoptive transfer of labelled neutrophils in C57BL/6 mice before surgery resulted in higher fluorescence intensities over the ischaemic hemisphere in tMCAO mice with NIRF imaging when compared with controls, corroborated by ex vivo detection of labelled neutrophils using fluorescence microscopy. NIRF imaging showed that neutrophils started to accumulate immediately after tMCAO, peaking at 18 h, and were still visible until 48 h after reperfusion. Our data revealed accumulation of neutrophils also in extracranial tissue, indicating damage in the external carotid artery territory in the tMCAO model. Antibody-mediated inhibition of α4-integrins did reduce fluorescence signals at 18 and 24, but not at 48 h after reperfusion, compared with control treatment animals. Antibody treatment reduced cerebral lesion volumes by 19%. In conclusion, the non-invasive nature of NIRF imaging allows studying the dynamics of neutrophil recruitment and its modulation by targeted interventions in the mouse brain after transient experimental cerebral ischaemia.

  5. Non-invasive cardiac imaging techniques and vascular tools for the assessment of cardiovascular disease in type 2 diabetes mellitus.

    PubMed

    Djaberi, R; Beishuizen, E D; Pereira, A M; Rabelink, T J; Smit, J W; Tamsma, J T; Huisman, M V; Jukema, J W

    2008-09-01

    Cardiovascular disease is the major cause of mortality in type 2 diabetes mellitus. The criteria for the selection of those asymptomatic patients with type 2 diabetes who should undergo cardiac screening and the therapeutic consequences of screening remain controversial. Non-invasive techniques as markers of atherosclerosis and myocardial ischaemia may aid risk stratification and the implementation of tailored therapy for the patient with type 2 diabetes. In the present article we review the literature on the implementation of non-invasive vascular tools and cardiac imaging techniques in this patient group. The value of these techniques as endpoints in clinical trials and as risk estimators in asymptomatic diabetic patients is discussed. Carotid intima-media thickness, arterial stiffness and flow-mediated dilation are abnormal long before the onset of type 2 diabetes. These vascular tools are therefore most likely to be useful for the identification of 'at risk' patients during the early stages of atherosclerotic disease. The additional value of these tools in risk stratification and tailored therapy in type 2 diabetes remains to be proven. Cardiac imaging techniques are more justified in individuals with a strong clinical suspicion of advanced coronary heart disease (CHD). Asymptomatic myocardial ischaemia can be detected by stress echocardiography and myocardial perfusion imaging. The more recently developed non-invasive multi-slice computed tomography angiography is recommended for exclusion of CHD, and can therefore be used to screen asymptomatic patients with type 2 diabetes, but has the associated disadvantages of high radiation exposure and costs. Therefore, we propose an algorithm for the screening of asymptomatic diabetic patients, the first step of which consists of coronary artery calcium score assessment and exercise ECG.

  6. Non-invasive imaging and cellular tracking of pulmonary emboli by near-infrared fluorescence and positron-emission tomography

    PubMed Central

    Page, Michael J.; Lourenço, André L.; David, Tovo; LeBeau, Aaron M.; Cattaruzza, Fiore; Castro, Helena C.; VanBrocklin, Henry F.; Coughlin, Shaun R.; Craik, Charles S.

    2015-01-01

    Functional imaging of proteolytic activity is an emerging strategy to quantify disease and response to therapy at the molecular level. We present a new peptide-based imaging probe technology that advances these goals by exploiting enzymatic activity to deposit probes labelled with near-infrared (NIR) fluorophores or radioisotopes in cell membranes of disease-associated proteolysis. This strategy allows for non-invasive detection of protease activity in vivo and ex vivo by tracking deposited probes in tissues. We demonstrate non-invasive detection of thrombin generation in a murine model of pulmonary embolism using our protease-activated peptide probes in microscopic clots within the lungs with NIR fluorescence optical imaging and positron-emission tomography. Thrombin activity is imaged deep in tissue and tracked predominantly to platelets within the lumen of blood vessels. The modular design of our probes allows for facile investigation of other proteases, and their contributions to disease by tailoring the protease activation and cell-binding elements. PMID:26423607

  7. Non-invasive fluorescent-protein imaging of orthotopic pancreatic-cancer-patient tumorgraft progression in nude mice.

    PubMed

    Suetsugu, Atsushi; Katz, Matthew; Fleming, Jason; Truty, Mark; Thomas, Ryan; Saji, Shigetoyo; Moriwaki, Hisataka; Bouvet, Michael; Hoffman, Robert M

    2012-08-01

    In order to individualize and therefore have more effective treatment for pancreatic cancer, we have developed a multicolor, imageable, orthotopic mouse model for individual patients with pancreatic cancer by passaging their tumors through transgenic nude mice expressing green fluorescent protein (GFP) and red fluorescent protein (RFP). The tumors acquired brightly fluorescent stroma from the transgenic host mice, which was stably associated with the tumors through multiple passages. In the present study, pancreatic cancer patient tumor specimens were initially established in NOD.CB17-Prkdc(scid)/NcrCrl (NOD/SCID) mice. The tumors were then passaged orthotopically into transgenic nude mice ubiquitously expressing GFP and subsequently to nude mice ubiquitously expressing RFP. The tumors, with very bright GFP and RFP stroma, were then orthotopically passaged to non-transgenic nude mice. It was possible to image the brightly fluorescent tumors non-invasively longitudinally as they progressed in the non-transgenic nude mice. This non-invasive imageable tumorgraft model will be valuable to screen for effective treatment options for individual patients with pancreatic cancer, as well as for the discovery of improved agents for this treatment-resistant disease.

  8. Application of fluorescence spectroscopy and multispectral imaging for non-invasive estimation of GFP transfection efficiency

    NASA Astrophysics Data System (ADS)

    Tamošiūnas, M.; Jakovels, D.; Lihačovs, A.; Kilikevičius, A.; Baltušnikas, J.; Kadikis, R.; Šatkauskas, S.

    2014-10-01

    Electroporation and ultrasound induced sonoporation has been showed to induce plasmid DNA transfection to the mice tibialis cranialis muscle. It offers new prospects for gene therapy and cancer treatment. However, numerous experimental data are still needed to deliver the plausible explanation of the mechanisms governing DNA electro- or sono-transfection, as well as to provide the updates on transfection protocols for transfection efficiency increase. In this study we aimed to apply non-invasive optical diagnostic methods for the real time evaluation of GFP transfection levels at the reduced costs for experimental apparatus and animal consumption. Our experimental set-up allowed monitoring of GFP levels in live mice tibialis cranialis muscle and provided the parameters for DNA transfection efficiency determination.

  9. Non-invasive continuous imaging of drug release from soy-based skin equivalent using wide-field interferometry

    NASA Astrophysics Data System (ADS)

    Gabai, Haniel; Baranes-Zeevi, Maya; Zilberman, Meital; Shaked, Natan T.

    2013-04-01

    We propose an off-axis interferometric imaging system as a simple and unique modality for continuous, non-contact and non-invasive wide-field imaging and characterization of drug release from its polymeric device used in biomedicine. In contrast to the current gold-standard methods in this field, usually based on chromatographic and spectroscopic techniques, our method requires no user intervention during the experiment, and only one test-tube is prepared. We experimentally demonstrate imaging and characterization of drug release from soy-based protein matrix, used as skin equivalent for wound dressing with controlled anesthetic, Bupivacaine drug release. Our preliminary results demonstrate the high potential of our method as a simple and low-cost modality for wide-field imaging and characterization of drug release from drug delivery devices.

  10. A New Imaging Platform for Visualizing Biological Effects of Non-Invasive Radiofrequency Electric-Field Cancer Hyperthermia

    PubMed Central

    Corr, Stuart J.; Shamsudeen, Sabeel; Vergara, Leoncio A.; Ho, Jason Chak-Shing; Ware, Matthew J.; Keshishian, Vazrik; Yokoi, Kenji; Savage, David J.; Meraz, Ismail M.; Kaluarachchi, Warna; Cisneros, Brandon T.; Raoof, Mustafa; Nguyen, Duy Trac; Zhang, Yingchun; Wilson, Lon J.; Summers, Huw; Rees, Paul; Curley, Steven A.; Serda, Rita E.

    2015-01-01

    Herein, we present a novel imaging platform to study the biological effects of non-invasive radiofrequency (RF) electric field cancer hyperthermia. This system allows for real-time in vivo intravital microscopy (IVM) imaging of radiofrequency-induced biological alterations such as changes in vessel structure and drug perfusion. Our results indicate that the IVM system is able to handle exposure to high-power electric-fields without inducing significant hardware damage or imaging artifacts. Furthermore, short durations of low-power (< 200 W) radiofrequency exposure increased transport and perfusion of fluorescent tracers into the tumors at temperatures below 41°C. Vessel deformations and blood coagulation were seen for tumor temperatures around 44°C. These results highlight the use of our integrated IVM-RF imaging platform as a powerful new tool to visualize the dynamics and interplay between radiofrequency energy and biological tissues, organs, and tumors. PMID:26308617

  11. Non-Invasive Imaging Demonstrates Clinical Features of Ankylosing Spondylitis in a Rat Adjuvant Model: a Case Study

    PubMed Central

    Dawson, J.; Kolbinger, F.; Kramer, I.; Beckmann, N.

    2016-01-01

    Main features of ankylosing spondylitis like inflammatory erosive osteopenia and bony overgrowth are recapitulated in rats challenged with complete Freund’s adjuvant. In vivo changes induced in the rat spine were followed longitudinally by magnetic resonance imaging (MRI) and assessed terminally by micro-computerized tomography (micro-CT) and histology. Signals reflecting inflammation were detected by MRI at levels L5-L6 throughout the experiment, peaking at day 27 after adjuvant. Bone erosion and formation occurred from this time point onward, as confirmed by micro-CT. Histology confirmed the inflammation and bone remodeling. The present study demonstrates the potential of imaging for longitudinal assessments of spinal changes in this animal model and the excellent correlation between in vivo images and histology underlines its fundamental role in the validation of non-invasive imaging. PMID:28076929

  12. Non-invasive localization of thymol accumulation in Carum copticum (Apiaceae) fruits by chemical shift selective magnetic resonance imaging.

    PubMed

    Gersbach, P V; Reddy, N

    2002-08-01

    Magnetic resonance imaging was used to localize the site of essential oil accumulation in fruit of Carum copticum L. (Apiaceae). A chemical shift method is described that utilized the spectral properties of the aromatic monoterpene thymol, the major component of the essential oil, to image thymol selectively. The presence of essential oil secretory structures in the fruit and an essential oil containing a high proportion of thymol were confirmed with optical microscopy and gas chromatography-mass spectrometry, respectively. Selective imaging of whole C. copticum fruits showed that thymol accumulation was localized to the secretory structures (canals) situated in the fruit wall. The technique was considered non-invasive as the seeds used in the imaging experiments remained intact and viable.

  13. Simplified Models of Non-Invasive Fractional Flow Reserve Based on CT Images

    PubMed Central

    Zhang, Jun-Mei; Zhong, Liang; Luo, Tong; Lomarda, Aileen Mae; Huo, Yunlong; Yap, Jonathan; Lim, Soo Teik; Tan, Ru San; Wong, Aaron Sung Lung; Tan, Jack Wei Chieh; Yeo, Khung Keong; Fam, Jiang Ming; Keng, Felix Yung Jih; Wan, Min; Su, Boyang; Zhao, Xiaodan; Allen, John Carson; Kassab, Ghassan S.; Chua, Terrance Siang Jin; Tan, Swee Yaw

    2016-01-01

    Invasive fractional flow reserve (FFR) is the gold standard to assess the functional coronary stenosis. The non-invasive assessment of diameter stenosis (DS) using coronary computed tomography angiography (CTA) has high false positive rate in contrast to FFR. Combining CTA with computational fluid dynamics (CFD), recent studies have shown promising predictions of FFRCT for superior assessment of lesion severity over CTA alone. The CFD models tend to be computationally expensive, however, and require several hours for completing analysis. Here, we introduce simplified models to predict noninvasive FFR at substantially less computational time. In this retrospective pilot study, 21 patients received coronary CTA. Subsequently a total of 32 vessels underwent invasive FFR measurement. For each vessel, FFR based on steady-state and analytical models (FFRSS and FFRAM, respectively) were calculated non-invasively based on CTA and compared with FFR. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value were 90.6% (87.5%), 80.0% (80.0%), 95.5% (90.9%), 88.9% (80.0%) and 91.3% (90.9%) respectively for FFRSS (and FFRAM) on a per-vessel basis, and were 75.0%, 50.0%, 86.4%, 62.5% and 79.2% respectively for DS. The area under the receiver operating characteristic curve (AUC) was 0.963, 0.954 and 0.741 for FFRSS, FFRAM and DS respectively, on a per-patient level. The results suggest that the CTA-derived FFRSS performed well in contrast to invasive FFR and they had better diagnostic performance than DS from CTA in the identification of functionally significant lesions. In contrast to FFRCT, FFRSS requires much less computational time. PMID:27187726

  14. Reflectance confocal microscopy and dermoscopy for in vivo, non-invasive skin imaging of superficial basal cell carcinoma

    PubMed Central

    GHITA, MIHAELA A.; CARUNTU, CONSTANTIN; ROSCA, ADRIAN E.; KALESHI, HARILLAQ; CARUNTU, ANA; MORARU, LILIANA; DOCEA, ANCA OANA; ZURAC, SABINA; BODA, DANIEL; NEAGU, MONICA; SPANDIDOS, DEMETRIOS A.; TSATSAKIS, ARISTIDIS M.

    2016-01-01

    Superficial basal cell carcinoma (sBCC) is the second most frequent histological type of basal cell carcinoma (BCC), usually requiring a skin biopsy to confirm the diagnosis. It usually appears on the upper trunk and shoulders as erythematous and squamous lesions. Although it has a slow growth and seldom metastasizes, early diagnosis and management are of crucial importance in preventing local invasion and subsequent disfigurement. Dermoscopy is nowadays an indispensable tool for the dermatologist when evaluating skin tumors. Reflectance confocal microscopy (RCM) is a novel imaging technique that allows the non-invasive, in vivo quasi-microscopic morphological and dynamic assessment of superficial skin tumors. Moreover, it offers the advantage of performing infinite repeatable determinations to monitor disease progression and non-surgical treatment for sBCC. Herein, we present three lesions of sBCC evaluated using in vivo and non-invasive imaging techniques, emphasizing the usefulness of combining RCM with dermoscopy for increasing the diagnostic accuracy of sBCC. PMID:27123056

  15. Spectroscopic imaging of blood vessels only near the skin surface for non-invasive blood glucose measurement

    NASA Astrophysics Data System (ADS)

    Fujiwara, Masaru; Sato, Shun; Abeygunawardhana, Pradeep K. W.; Suzuki, Satoru; Nishiyama, Akira; Wada, Kenji; Ishimaru, Ichiro

    2015-07-01

    To realize the non-invasive blood glucose measurement, it will be effective to acquire the spectroscopic imaging of blood vessels only near the skin surface for eliminating other biological-component's disturbances. Our proposed imaging-type 2-dimensional Fourier spectroscopic imaging can limit the measuring depth into focal plane with high light detection sensitivity. Thus, the proposed method will be suitable for measuring only near the skin surface with detecting weak reflected light from inner biomembrane. But reflectance of skin surface is more than 1000 times larger than inner skin's reflectance. Paying attention on Fresnel reflection, fingers what were illuminated by p-polarized beam from Brewster's angle were observed with crossed-Nicol dark field optics. We successfully acquired spectroscopic characteristics of hemoglobin at vein area near the skin surface.

  16. Non-invasive cardiac pacing with image-guided focused ultrasound

    PubMed Central

    Marquet, Fabrice; Bour, Pierre; Vaillant, Fanny; Amraoui, Sana; Dubois, Rémi; Ritter, Philippe; Haïssaguerre, Michel; Hocini, Mélèze; Bernus, Olivier; Quesson, Bruno

    2016-01-01

    Currently, no non-invasive cardiac pacing device acceptable for prolonged use in conscious patients exists. High Intensity Focused Ultrasound (HIFU) can be used to perform remote pacing using reversibility of electromechanical coupling of cardiomyocytes. Here we described an extracorporeal cardiac stimulation device and study its efficacy and safety. We conducted experiments ex vivo and in vivo in a large animal model (pig) to evaluate clinical potential of such a technique. The stimulation threshold was determined in 10 different ex vivo hearts and different clinically relevant electrical effects such as consecutive stimulations of different heart chambers with a single ultrasonic probe, continuous pacing or the inducibility of ventricular tachycardia were shown. Using ultrasonic contrast agent, consistent cardiac stimulation was achievable in vivo for up to 1 hour sessions in 4 different animals. No damage was observed in inversion-recovery MR sequences performed in vivo in the 4 animals. Histological analysis revealed no differences between stimulated and control regions, for all ex vivo and in vivo cases. PMID:27827415

  17. Non-invasive cardiac pacing with image-guided focused ultrasound

    NASA Astrophysics Data System (ADS)

    Marquet, Fabrice; Bour, Pierre; Vaillant, Fanny; Amraoui, Sana; Dubois, Rémi; Ritter, Philippe; Haïssaguerre, Michel; Hocini, Mélèze; Bernus, Olivier; Quesson, Bruno

    2016-11-01

    Currently, no non-invasive cardiac pacing device acceptable for prolonged use in conscious patients exists. High Intensity Focused Ultrasound (HIFU) can be used to perform remote pacing using reversibility of electromechanical coupling of cardiomyocytes. Here we described an extracorporeal cardiac stimulation device and study its efficacy and safety. We conducted experiments ex vivo and in vivo in a large animal model (pig) to evaluate clinical potential of such a technique. The stimulation threshold was determined in 10 different ex vivo hearts and different clinically relevant electrical effects such as consecutive stimulations of different heart chambers with a single ultrasonic probe, continuous pacing or the inducibility of ventricular tachycardia were shown. Using ultrasonic contrast agent, consistent cardiac stimulation was achievable in vivo for up to 1 hour sessions in 4 different animals. No damage was observed in inversion-recovery MR sequences performed in vivo in the 4 animals. Histological analysis revealed no differences between stimulated and control regions, for all ex vivo and in vivo cases.

  18. Image-assisted non-invasive and dynamic biomechanical analysis of human joints.

    PubMed

    Muhit, Abdullah A; Pickering, Mark R; Scarvell, Jennifer M; Ward, Tom; Smith, Paul N

    2013-07-07

    Kinematic analysis provides a strong link between musculoskeletal injuries, chronic joint conditions, treatment planning/monitoring and prosthesis design/outcome. However, fast and accurate 3D kinematic analysis still remains a challenge in order to translate this procedure into clinical scenarios. 3D computed tomography (CT) to 2D single-plane fluoroscopy registration is a promising non-invasive technology for biomechanical examination of human joints. Although this technique has proven to be very precise in terms of in-plane translation and rotation measurements, out-of-plane motion estimations have been a difficulty so far. Therefore, to enable this technology into clinical translation, precise and fast estimation of both in-plane and out-of-plane movements is crucial, which is the aim of this paper. Here, a fast and accurate 3D/2D registration technique is proposed to evaluate biomechanical/kinematic analysis. The proposed algorithm utilizes a new multi-modal similarity measure called 'sum of conditional variances', a coarse-to-fine Laplacian of Gaussian filtering approach for robust gradient-descent optimization and a novel technique for the analytic calculation of the required gradients for out-of-plane rotations. Computer simulations and in vitro experiments showed that the new approach was robust in terms of the capture range, required significantly less iterations to converge and achieved good registration and kinematic accuracy when compared to existing techniques and to the 'gold-standard' Roentgen stereo analysis.

  19. Non-invasive Detection of Breast Cancer Lymph Node Metastasis using Carbonic Anhydrases IX and XII Targeted Imaging Probes

    PubMed Central

    Tafreshi, Narges K.; Bui, Marilyn M.; Bishop, Kellsey; Lloyd, Mark C.; Enkemann, Steven A.; Lopez, Alexis S.; Abrahams, Dominique; Carter, Bradford W.; Vagner, Josef; Grobmyer, Stephen R.; Gillies, Robert J.; Morse, David L.

    2014-01-01

    Purpose To develop targeted molecular imaging probes for the non-invasive detection of breast cancer lymph node metastasis. Methods Six cell surface or secreted markers were identified by expression profiling and from the literature as being highly expressed in breast cancer lymph node metastases. Two of these markers were cell surface carbonic anhydrase isozymes (CAIX and/or CAXII) and were validated for protein expression by immunohistochemistry (IHC) of patient tissue samples on a breast cancer tissue microarray containing 47 normal breast tissue samples, 42 ductal carcinoma in situ, 43 invasive ductal carcinomas without metastasis, 46 invasive ductal carcinomas with metastasis and 49 lymph node macrometastases of breast carcinoma. Targeted probes were developed by conjugation of CAIX and CAXII specific monoclonal antibodies (mAbs) to a near-infrared fluorescent dye. Results Together, these two markers were expressed in 100% of the lymph node metastases surveyed. Selectivity of the imaging probes were confirmed by intravenous injection into nude mice bearing mammary fat pad tumors of marker expressing cells, and non-expressing cells or by pre-injection of unlabeled antibody. Imaging of LN metastases showed that peritumorally-injected probes detected nodes harboring metastatic tumor cells. As few as 1,000 cells were detected, as determined by implanting, under ultrasound guidance, a range in number of CAIX and CAXII expressing cells into the axillary LNs. Conclusion These imaging probes have potential for non-invasive staging of breast cancer in the clinic and elimination of unneeded surgery, which is costly and associated with morbidities. PMID:22016510

  20. 4DCBCT-based motion modeling and 3D fluoroscopic image generation for lung cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Dhou, Salam; Hurwitz, Martina; Mishra, Pankaj; Berbeco, Ross; Lewis, John

    2015-03-01

    A method is developed to build patient-specific motion models based on 4DCBCT images taken at treatment time and use them to generate 3D time-varying images (referred to as 3D fluoroscopic images). Motion models are built by applying Principal Component Analysis (PCA) on the displacement vector fields (DVFs) estimated by performing deformable image registration on each phase of 4DCBCT relative to a reference phase. The resulting PCA coefficients are optimized iteratively by comparing 2D projections captured at treatment time with projections estimated using the motion model. The optimized coefficients are used to generate 3D fluoroscopic images. The method is evaluated using anthropomorphic physical and digital phantoms reproducing real patient trajectories. For physical phantom datasets, the average tumor localization error (TLE) and (95th percentile) in two datasets were 0.95 (2.2) mm. For digital phantoms assuming superior image quality of 4DCT and no anatomic or positioning disparities between 4DCT and treatment time, the average TLE and the image intensity error (IIE) in six datasets were smaller using 4DCT-based motion models. When simulating positioning disparities and tumor baseline shifts at treatment time compared to planning 4DCT, the average TLE (95th percentile) and IIE were 4.2 (5.4) mm and 0.15 using 4DCT-based models, while they were 1.2 (2.2) mm and 0.10 using 4DCBCT-based ones, respectively. 4DCBCT-based models were shown to perform better when there are positioning and tumor baseline shift uncertainties at treatment time. Thus, generating 3D fluoroscopic images based on 4DCBCT-based motion models can capture both inter- and intra- fraction anatomical changes during treatment.

  1. Non-invasive Measurement of Thermal Diffusivity Using High-Intensity Focused Ultrasound and Through-Transmission Ultrasonic Imaging.

    PubMed

    Yeshurun, Lilach; Azhari, Haim

    2016-01-01

    Thermal diffusivity at the site ablated by high-intensity focused ultrasound (HIFU) plays an important role in the final therapeutic outcome, as it influences the temperature's spatial and temporal distribution. Moreover, as tissue thermal diffusivity is different in tumors as compared with normal tissue, it could also potentially be used as a new source of imaging contrast. The aim of this study was to examine the feasibility of combining through-transmission ultrasonic imaging and HIFU to estimate thermal diffusivity non-invasively. The concept was initially evaluated using a computer simulation. Then it was experimentally tested on phantoms made of agar and ex vivo porcine fat. A computerized imaging system combined with a HIFU system was used to heat the phantoms to temperatures below 42°C to avoid irreversible damage. Through-transmission scanning provided the time-of-flight values in a region of interest during its cooling process. The time-of-flight values were consequently converted into mean values of speed of sound. Using the speed-of-sound profiles along with the developed model, we estimated the changes in temperature profiles over time. These changes in temperature profiles were then used to calculate the corresponding thermal diffusivity of the studied specimen. Thermal diffusivity for porcine fat was found to be lower by one order of magnitude than that obtained for agar (0.313×10(-7)m(2)/s vs. 4.83×10(-7)m(2)/s, respectively, p < 0.041). The fact that there is a substantial difference between agar and fat implies that non-invasive all-ultrasound thermal diffusivity mapping is feasible. The suggested method may particularly be suitable for breast scanning.

  2. Dynamic imaging of pulmonary ventilation. Description of a novel digital fluoroscopic system.

    PubMed

    Kiuru, A; Svedström, E; Kuuluvainen, I

    1991-03-01

    A new fluoroscopic imaging device consisting of an AT-microcomputer and a digital image memory unit has been used in experimental and clinical ventilation studies during a 2-year period. Digital images with 256 shades of gray were collected during one to 3 ventilation cycles at the rate of 6 to 25 images/s and stored on an optical laser disc. Both subtracted time interval difference (TID-) images and images relative, for example, to the mean image of the cycle (REL-images) were produced. The series of images could also be evaluated dynamically using animation sequences or analyzed using region of interest calculations. The method gave dynamic information with adequate spatial resolution and was easy to use in clinical practice. The radiation dose was kept low due to the high kilovoltage and heavy beam filtration technique. In experimental studies the software enabled flexible measurements of physiological pulmonary parameters.

  3. In vivo and in vitro tracking of erosion in biodegradable materials using non-invasive fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Artzi, Natalie; Oliva, Nuria; Puron, Cristina; Shitreet, Sagi; Artzi, Shay; Bon Ramos, Adriana; Groothuis, Adam; Sahagian, Gary; Edelman, Elazer R.

    2011-09-01

    The design of erodible biomaterials relies on the ability to program the in vivo retention time, which necessitates real-time monitoring of erosion. However, in vivo performance cannot always be predicted by traditional determination of in vitro erosion, and standard methods sacrifice samples or animals, preventing sequential measures of the same specimen. We harnessed non-invasive fluorescence imaging to sequentially follow in vivo material-mass loss to model the degradation of materials hydrolytically (PEG:dextran hydrogel) and enzymatically (collagen). Hydrogel erosion rates in vivo and in vitro correlated, enabling the prediction of in vivo erosion of new material formulations from in vitro data. Collagen in vivo erosion was used to infer physiologic in vitro conditions that mimic erosive in vivo environments. This approach enables rapid in vitro screening of materials, and can be extended to simultaneously determine drug release and material erosion from a drug-eluting scaffold, or cell viability and material fate in tissue-engineering formulations.

  4. Analysis of microparticle penetration into human and porcine skin: non-invasive imaging with multiphoton excitation microscopy

    NASA Astrophysics Data System (ADS)

    Mulholland, William J.; Kendall, Mark A.; Bellhouse, Brian J.; White, Nick

    2002-06-01

    At the University of Oxford and PowderJect Pharmaceuticals plc, a unique form of needle-free injection technology has been developed. Powdered vaccines and drugs in micro-particle form are accelerated in a high-speed gas flow to sufficient velocity to enter the skin, subsequently achieving a pharmaceutical effect. To optimize the delivery of vaccines and drugs with this method a detailed understanding of the interactive processes that occur between the microparticles and the skin is necessary. Investigations to date of micro-particle delivery into excised human and animal tissue have involved image analyses of histology sections. In the present study, a series of investigations were conducted on excised human and porcine skin using the technique of Multi-Photon fluorescence excitation Microscopy (MPM) to image particles and skin structures post-penetration. Micro-particles of various size and composition were imaged with infrared laser excitation. Three-dimensional images of stratum corneum and epidermal cell deformation due to micro-particle penetration were obtained. Measurements of micro-particle penetration depth taken from z-scan image stacks were used to successfully quantify micro-particle distribution within the skin, without invasively disrupting the skin target. This study has shown that MPM has great potential for the non-invasive imaging of particle skin interactive processes that occur with the transdermal delivery of powdered micro-particle vaccines and drugs.

  5. In Vivo Non Invasive Molecular Imaging for Immune Cell Tracking in Small Animals

    PubMed Central

    Hong, Kee-Jong

    2012-01-01

    Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic wholebody imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments. PMID:23396713

  6. Non-invasive imaging of breast cancer with diffusing near-infrared light

    NASA Astrophysics Data System (ADS)

    Konecky, Soren D.

    Diffuse optical tomography (DOT) is a new medical imaging technique that combines biomedical optics with the principles of computed tomography. We use DOT to quantitatively reconstruct images of complex phantoms with millimeter sized features located centimeters deep within a highly-scattering medium. A non-contact instrument is employed to collect large data sets consisting of greater than 107 source-detector pairs. Images are reconstructed using a fast image reconstruction algorithm based on an analytic solution to the inverse scattering problem for diffuse light. We also describe a next generation DOT breast imaging device for frequency domain transmission data acquisition in the parallel plate geometry. Frequency domain heterodyne measurements are made by intensity modulating a continuous wave laser source with an electro-optic modulator (EOM) and detecting the transmitted light with a gain-modulated image intensifier coupled to a CCD. Finally, we acquire and compare three-dimensional tomographic breast images of three females with suspicious masses using DOT and Positron Emission Tomography (PET). Co-registration of DOT and PET images is facilitated by a mutual information maximization algorithm. We also compare DOT and whole-body PET images of 14 patients with breast abnormalities. Positive correlations are found between both total hemoglobin concentration and tissue scattering, and fluorodeoxyglucose (18F-FDG) uptake.

  7. Non-invasive imaging and monitoring of rodent retina using simultaneous dual-band optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Cimalla, Peter; Burkhardt, Anke; Walther, Julia; Hoefer, Aline; Wittig, Dierk; Funk, Richard; Koch, Edmund

    2011-03-01

    Spectral domain dual-band optical coherence tomography for simultaneous imaging of rodent retina in the 0.8 μm and 1.3 μm wavelength region and non-invasive monitoring of the posterior eye microstructure in the field of retinal degeneration research is demonstrated. The system is illuminated by a supercontinuum laser source and allows three-dimensional imaging with high axial resolution better than 3.8 μm and 5.3 μm in tissue at 800 nm and 1250 nm, respectively, for precise retinal thickness measurements. A fan-shaped scanning pattern with the pivot point close to the eye's pupil and a contact lens are applied to obtain optical access to the eye's fundus. First in vivo experiments in a RCS (royal college of surgeons) rat model with gene-related degeneration of the photoreceptor cells show good visibility of the retinal microstructure with sufficient contrast for thickness measurement of individual retinal layers. An enhanced penetration depth at 1250 nm is clearly identifiable revealing sub-choroidal structures that are not visible at 800 nm. Furthermore, additional simultaneous imaging at 1250 nm improves image quality by frequency compounding speckle noise reduction. These results are encouraging for time course studies of the rodent retina concerning its development related to disease progression and treatment response.

  8. Non-invasive PET imaging of brain inflammation at disease onset predicts spontaneous recurrent seizures and reflects comorbidities.

    PubMed

    Bertoglio, Daniele; Verhaeghe, Jeroen; Santermans, Eva; Amhaoul, Halima; Jonckers, Elisabeth; Wyffels, Leonie; Van Der Linden, Annemie; Hens, Niel; Staelens, Steven; Dedeurwaerdere, Stefanie

    2017-03-01

    Brain inflammation is an important factor in the conversion of a healthy brain into an epileptic one, a phenomenon known as epileptogenesis, offering a new entry point for prognostic tools. The development of anti-epileptogenic therapies to treat before or at disease onset is hampered by our inability to predict the severity of the disease outcome. In a rat model of temporal lobe epilepsy we aimed to assess whether in vivo non-invasive imaging of brain inflammation at disease onset was predictive of spontaneous recurrent seizures (SRS) frequency and severity of depression-like and sensorimotor-related comorbidities. To this end, translocator protein, a biomarker of inflammation, was imaged by means of positron emission tomography (PET) 2 and 4weeks post-status epilepticus using [(18)F]-PBR111. Translocator protein was highly upregulated 2weeks post-status epilepticus in limbic structures (up to 2.1-fold increase compared to controls in temporal lobe, P<0.001), whereas 4weeks post-status epilepticus, upregulation decreased (up to 1.6-fold increase compared to controls in temporal lobe, P<0.01) and was only apparent in a subset of these regions. Animals were monitored with video-electroencephalography during all stages of disease (acute, latent - first seizures appearing around 2weeks post-status epilepticus - and chronic phases), for a total of 12weeks, in order to determine SRS frequency for each subject (range 0.00-0.83SRS/day). We found that regional PET uptake at 2 and 4weeks post-status epilepticus correlated with the severity of depression-like and sensorimotor-related comorbidities during chronic epilepsy (P<0.05 for each test). Regional PET imaging did not correlate with SRS frequency, however, by applying a multivariate data-driven modeling approach based on translocator protein PET imaging at 2weeks post-status epilepticus, we accurately predicted the frequency of SRS (R=0.92; R(2)=0.86; P<0.0001) at the onset of epilepsy. This study not only demonstrates

  9. Multispectral imaging approach for simplified non-invasive in-vivo evaluation of gingival erythema

    NASA Astrophysics Data System (ADS)

    Eckhard, Timo; Valero, Eva M.; Nieves, Juan L.; Gallegos-Rueda, José M.; Mesa, Francisco

    2012-03-01

    Erythema is a common visual sign of gingivitis. In this work, a new and simple low-cost image capture and analysis method for erythema assessment is proposed. The method is based on digital still images of gingivae and applied on a pixel-by-pixel basis. Multispectral images are acquired with a conventional digital camera and multiplexed LED illumination panels at 460nm and 630nm peak wavelength. An automatic work-flow segments teeth from gingiva regions in the images and creates a map of local blood oxygenation levels, which relates to the presence of erythema. The map is computed from the ratio of the two spectral images. An advantage of the proposed approach is that the whole process is easy to manage by dental health care professionals in clinical environment.

  10. Real-time image-processing algorithm for markerless tumour tracking using X-ray fluoroscopic imaging

    PubMed Central

    2014-01-01

    Objective: To ensure accuracy in respiratory-gating treatment, X-ray fluoroscopic imaging is used to detect tumour position in real time. Detection accuracy is strongly dependent on image quality, particularly positional differences between the patient and treatment couch. We developed a new algorithm to improve the quality of images obtained in X-ray fluoroscopic imaging and report the preliminary results. Methods: Two oblique X-ray fluoroscopic images were acquired using a dynamic flat panel detector (DFPD) for two patients with lung cancer. The weighting factor was applied to the DFPD image in respective columns, because most anatomical structures, as well as the treatment couch and port cover edge, were aligned in the superior–inferior direction when the patient lay on the treatment couch. The weighting factors for the respective columns were varied until the standard deviation of the pixel values within the image region was minimized. Once the weighting factors were calculated, the quality of the DFPD image was improved by applying the factors to multiframe images. Results: Applying the image-processing algorithm produced substantial improvement in the quality of images, and the image contrast was increased. The treatment couch and irradiation port edge, which were not related to a patient's position, were removed. The average image-processing time was 1.1 ms, showing that this fast image processing can be applied to real-time tumour-tracking systems. Conclusion: These findings indicate that this image-processing algorithm improves the image quality in patients with lung cancer and successfully removes objects not related to the patient. Advances in knowledge: Our image-processing algorithm might be useful in improving gated-treatment accuracy. PMID:24661056

  11. Imaging-Based Methods for Non-invasive Assessment of Bone Properties Influenced by Mechanical Loading.

    PubMed

    Macintyre, Norma J; Lorbergs, Amanda L

    2012-01-01

    Purpose: To describe the most common in vivo imaging-based research tools used to assess bone properties that are influenced by mechanical loading associated with exercise, habitual physical activity, or disease states. Bone is a complex metabolically active tissue that adapts to changes in mechanical loading by altering the amount and spatial organization of mineral. Method: Using a narrative review design, the authors provide an overview of bone biology and biomechanics to emphasize the importance of bone size scale, porosity, and degree of mineralization when interpreting measures acquired using quantitative ultrasound (QUS), dual-energy X-ray absorptiometry (DXA), computed tomography (CT), magnetic resonance imaging (MRI), and finite element analysis (FEA). For each imaging modality, basic imaging principles, typical outcome measures associated with changes in mechanical loading, and salient features for physiotherapists are described. Main Results: While each imaging modality has strengths and limitations, currently CT-based methods are best suited for determining the effects of mechanical loading on bone properties—particularly in the peripheral skeleton. Conclusions: Regardless of the imaging technology used, the physiotherapist must carefully consider the assumptions of the imaging-based method, the clinical context, the nature of the change in mechanical loading, and the expected time course for change in bone properties.

  12. In vivo photothermal optical coherence tomography for non-invasive imaging of endogenous absorption agents

    PubMed Central

    Makita, Shuichi; Yasuno, Yoshiaki

    2015-01-01

    In vivo photothermal optical coherence tomography (OCT) is demonstrated for cross-sectional imaging of endogenous absorption agents. In order to compromise the sensitivity, imaging speed, and sample motion immunity, a new photothermal detection scheme and phase processing method are developed. Phase-resolved swept-source OCT and fiber-pigtailed laser diode (providing excitation at 406 nm) are combined to construct a high-sensitivity photothermal OCT system. OCT probe and excitation beam coaxially illuminate and are focused on tissues. The photothermal excitation and detection procedure is designed to obtain high efficiency of photothermal effect measurement. The principle and method of depth-resolved cross-sectional imaging of absorption agents with photothermal OCT has been derived. The phase-resolved thermal expansion detection algorithm without motion artifact enables in vivo detection of photothermal effect. Phantom imaging with a blood phantom and in vivo human skin imaging are conducted. A phantom with guinea-pig blood as absorber has been scanned by the photothermal OCT system to prove the concept of cross-sectional absorption agent imaging. An in vivo human skin measurement is also performed with endogenous absorption agents. PMID:26137374

  13. In vivo photothermal optical coherence tomography for non-invasive imaging of endogenous absorption agents.

    PubMed

    Makita, Shuichi; Yasuno, Yoshiaki

    2015-05-01

    In vivo photothermal optical coherence tomography (OCT) is demonstrated for cross-sectional imaging of endogenous absorption agents. In order to compromise the sensitivity, imaging speed, and sample motion immunity, a new photothermal detection scheme and phase processing method are developed. Phase-resolved swept-source OCT and fiber-pigtailed laser diode (providing excitation at 406 nm) are combined to construct a high-sensitivity photothermal OCT system. OCT probe and excitation beam coaxially illuminate and are focused on tissues. The photothermal excitation and detection procedure is designed to obtain high efficiency of photothermal effect measurement. The principle and method of depth-resolved cross-sectional imaging of absorption agents with photothermal OCT has been derived. The phase-resolved thermal expansion detection algorithm without motion artifact enables in vivo detection of photothermal effect. Phantom imaging with a blood phantom and in vivo human skin imaging are conducted. A phantom with guinea-pig blood as absorber has been scanned by the photothermal OCT system to prove the concept of cross-sectional absorption agent imaging. An in vivo human skin measurement is also performed with endogenous absorption agents.

  14. Non-invasive imaging techniques in assessing non-alcoholic fatty liver disease: a current status of available methods

    PubMed Central

    Lăpădat, AM; Jianu, IR; Ungureanu, BS; Florescu, LM; Gheonea, DI; Sovaila, S; Gheonea, IA

    2017-01-01

    Non-alcoholic fatty liver disease (NAFLD) is an ailment affecting and increasing a number of people worldwide diagnosed via non-invasive imaging techniques, at a time when a minimum harm caused by medical procedures is rightfully emphasized, more sought after, than ever before. Liver steatosis should not be taken lightly even if its evolution is largely benign as it has the potential to develop into non-alcoholic steatohepatitis (NASH) or even more concerning, hepatic cirrhosis, and hepatocellular carcinoma (HCC). Traditionally, liver biopsy has been the standard for diagnosing this particular liver disease, but nowadays, a consistent number of imagistic methods are available for diagnosing hepatosteatosis and choosing the one appropriate to the clinical context is the key. Although different in sensitivity and specificity when it comes to determining the hepatic fat fraction (FF), these imaging techniques possessing a diverse availability, operating difficulty, cost, and reproducibility are invaluable to any modern physician. Ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), elastography, and spectroscopy will be discussed in order to lay out the advantages and disadvantages of their diagnostic potential and application. Although imagistics has given physicians a valuable insight into the means of managing NAFLD, the current methods are far from perfect, but given the time, they will surely be improved and the use of liver biopsy will be completely removed. PMID:28255371

  15. Non-invasive imaging techniques in assessing non-alcoholic fatty liver disease: a current status of available methods.

    PubMed

    Lăpădat, A M; Jianu, I R; Ungureanu, B S; Florescu, L M; Gheonea, D I; Sovaila, S; Gheonea, I A

    2017-01-01

    Non-alcoholic fatty liver disease (NAFLD) is an ailment affecting and increasing a number of people worldwide diagnosed via non-invasive imaging techniques, at a time when a minimum harm caused by medical procedures is rightfully emphasized, more sought after, than ever before. Liver steatosis should not be taken lightly even if its evolution is largely benign as it has the potential to develop into non-alcoholic steatohepatitis (NASH) or even more concerning, hepatic cirrhosis, and hepatocellular carcinoma (HCC). Traditionally, liver biopsy has been the standard for diagnosing this particular liver disease, but nowadays, a consistent number of imagistic methods are available for diagnosing hepatosteatosis and choosing the one appropriate to the clinical context is the key. Although different in sensitivity and specificity when it comes to determining the hepatic fat fraction (FF), these imaging techniques possessing a diverse availability, operating difficulty, cost, and reproducibility are invaluable to any modern physician. Ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), elastography, and spectroscopy will be discussed in order to lay out the advantages and disadvantages of their diagnostic potential and application. Although imagistics has given physicians a valuable insight into the means of managing NAFLD, the current methods are far from perfect, but given the time, they will surely be improved and the use of liver biopsy will be completely removed.

  16. The utilization of a non-invasive fluorescence imaging system to follow clinical dermatological MAL-PDT

    NASA Astrophysics Data System (ADS)

    Tyrrell, Jessica; Campbell, Sandra; Curnow, Alison

    2009-06-01

    This study employed a commercially available, non-invasive, fluorescence imaging system (Dyaderm, Biocam, Germany), to measure protoporphyrin IX (PpIX) concentration at several different stages during clinical dermatological methyl aminolevulinate photodynamic therapy (MAL-PDT). We validated the system prior to use to ensure that the PpIX changes witnessed were accurate and not due to environmental or user induced artifacts. The system was then employed to acquire color (morphological) and fluorescent (physiological) images simultaneously during dermatological PDT. Clinical data was collected from a range of licensed dermatological conditions (actinic keratosis, Bowen's disease and superficial basal cell carcinoma) during initial and subsequent PDT treatment cycles. The initial clinical data indicated that each type of licensed lesion considered responded in a similar manner following the application of Metvix (Galderma, U.K.) and the subsequent light irradiation (Aktilite, Galderma, U.K.). Images acquired three hours after Metvix application showed a significant increase in PpIX concentration within the lesion (P < 0.05), whilst PpIX levels in the surrounding normal tissue remained unaltered. After irradiation, the PpIX concentration was significantly decreased and returned to a level similar to the initial concentration originally observed. Lesions that received subsequent treatment cycles accumulated significantly less PpIX (P < 0.05) prior to irradiation.

  17. Multiphoton laser tomography and fluorescence lifetime imaging of basal cell carcinoma: morphologic features for non-invasive diagnostics.

    PubMed

    Seidenari, Stefania; Arginelli, Federica; Dunsby, Christopher; French, Paul; König, Karsten; Magnoni, Cristina; Manfredini, Marco; Talbot, Clifford; Ponti, Giovanni

    2012-11-01

    Multiphoton laser tomography (MPT) combined with fluorescence lifetime imaging (FLIM) is a non-invasive imaging technique, which gives access to the cellular and extracellular morphology of the skin. The aim of our study was to assess the sensitivity and specificity of MPT/FLIM descriptors for basal cell carcinoma (BCC), to improve BCC diagnosis and the identification of tumor margins. In the preliminary study, FLIM images referring to 35 BCCs and 35 healthy skin samples were evaluated for the identification of morphologic descriptors characteristic of BCC. In the main study, the selected parameters were blindly evaluated on a test set comprising 63 BCCs, 63 healthy skin samples and 66 skin lesions. Moreover, FLIM values inside a region of interest were calculated on 98 healthy skin and 98 BCC samples. In the preliminary study, three epidermal descriptors and 7 BCC descriptors were identified. The specificity of the diagnostic criteria versus 'other lesions' was extremely high, indicating that the presence of at least one BCC descriptor makes the diagnosis of 'other lesion' extremely unlikely. FLIM values referring to BCC cells significantly differed from those of healthy skin. In this study, we identified morphological and numerical descriptors enabling the differentiation of BCC from other skin disorders and its distinction from healthy skin in ex vivo samples. In future, MPT/FLIM may be applied to skin lesions to provide direct clinical guidance before biopsy and histological examination and for the identification of tumor margins allowing a complete surgical removal.

  18. Non-Invasive Magnetic Resonance Imaging of Nanoparticle Migration and Water Velocity Inside Sandstone

    NASA Astrophysics Data System (ADS)

    Phoenix, V. R.; Shukla, M.; Vallatos, A.; Riley, M. S.; Tellam, J. H.; Holmes, W. M.

    2015-12-01

    Manufactured nanoparticles (NPs) are already utilized in a diverse array of applications, including cosmetics, optics, medical technology, textiles and catalysts. Problematically, once in the natural environment, NPs can have a wide range of toxic effects. To protect groundwater from detrimental NPs we must be able to predict nanoparticle movement within the aquifer. The often complex transport behavior of nanoparticles ensures the development of NP transport models is not a simple task. To enhance our understanding of NP transport processes, we utilize novel magnetic resonance imaging (MRI) which enables us to look inside the rock and image the movement of nanoparticles within. For this, we use nanoparticles that are paramagnetic, making them visible to the MRI and enabling us to collect spatially resolved data from which we can develop more robust transport models. In this work, a core of Bentheimer sandstone (3 x 7 cm) was saturated with water and imaged inside a 7Tesla Bruker Biospec MRI. Firstly the porosity of the core was mapped using a MSME MRI sequence. Prior to imaging NP transport, the velocity of water (in absence on nanoparticles) was mapped using an APGSTE-RARE sequence. Nano-magnetite nanoparticles were then pumped into the core and their transport through the core was imaged using a RARE sequence. These images were calibrated using T2 parameter maps to provide fully quantitative maps of nanoparticle concentration at regular time intervals throughout the column (T2 being the spin-spin relaxation time of 1H nuclei). This work demonstrated we are able to spatially resolve porosity, water velocity and nanoparticle movement, inside rock, using a single technique (MRI). Significantly, this provides us with a unique and powerful dataset from which we are now developing new models of nanoparticle transport.

  19. Line-scanning Brillouin microscopy for rapid non-invasive mechanical imaging

    NASA Astrophysics Data System (ADS)

    Zhang, Jitao; Fiore, Antonio; Yun, Seok-Hyun; Kim, Hanyoup; Scarcelli, Giuliano

    2016-10-01

    Brillouin spectroscopy probes the mechanical properties of material by measuring the optical frequency shift induced by photon-phonon scattering interactions. In traditional configurations, Brillouin spectrometers measure only one point of the sample at a time. This results in long acquisition times for mechanical imaging of large areas. In this work, we demonstrate a parallel detection configuration where the Brillouin shift of hundreds of points in a line can be measured simultaneously. In mm-sized samples, this novel configuration effectively shortens the acquisition time of two-dimensional Brillouin imaging from hours to tens of seconds, thus making it a powerful technology for label-free mechanical characterization of tissue and biomaterials.

  20. Line-scanning Brillouin microscopy for rapid non-invasive mechanical imaging.

    PubMed

    Zhang, Jitao; Fiore, Antonio; Yun, Seok-Hyun; Kim, Hanyoup; Scarcelli, Giuliano

    2016-10-14

    Brillouin spectroscopy probes the mechanical properties of material by measuring the optical frequency shift induced by photon-phonon scattering interactions. In traditional configurations, Brillouin spectrometers measure only one point of the sample at a time. This results in long acquisition times for mechanical imaging of large areas. In this work, we demonstrate a parallel detection configuration where the Brillouin shift of hundreds of points in a line can be measured simultaneously. In mm-sized samples, this novel configuration effectively shortens the acquisition time of two-dimensional Brillouin imaging from hours to tens of seconds, thus making it a powerful technology for label-free mechanical characterization of tissue and biomaterials.

  1. Towards non-invasive diagnostic imaging of early-stage Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Viola, Kirsten L.; Sbarboro, James; Sureka, Ruchi; de, Mrinmoy; Bicca, Maíra A.; Wang, Jane; Vasavada, Shaleen; Satpathy, Sreyesh; Wu, Summer; Joshi, Hrushikesh; Velasco, Pauline T.; Macrenaris, Keith; Waters, E. Alex; Lu, Chang; Phan, Joseph; Lacor, Pascale; Prasad, Pottumarthi; Dravid, Vinayak P.; Klein, William L.

    2015-01-01

    One way to image the molecular pathology in Alzheimer's disease is by positron emission tomography using probes that target amyloid fibrils. However, these fibrils are not closely linked to the development of the disease. It is now thought that early-stage biomarkers that instigate memory loss are composed of Aβ oligomers. Here, we report a sensitive molecular magnetic resonance imaging contrast probe that is specific for Aβ oligomers. We attach oligomer-specific antibodies onto magnetic nanostructures and show that the complex is stable and binds to Aβ oligomers on cells and brain tissues to give a magnetic resonance imaging signal. When intranasally administered to an Alzheimer's disease mouse model, the probe readily reached hippocampal Aβ oligomers. In isolated samples of human brain tissue, we observed a magnetic resonance imaging signal that distinguished Alzheimer's disease from controls. Such nanostructures that target neurotoxic Aβ oligomers are potentially useful for evaluating the efficacy of new drugs and ultimately for early-stage Alzheimer's disease diagnosis and disease management.

  2. Multiresolution parametric estimation of transparent motions and denoising of fluoroscopic images.

    PubMed

    Auvray, Vincent; Liénard, Jean; Bouthemy, Patrick

    2005-01-01

    We describe a novel multiresolution parametric framework to estimate transparent motions typically present in X-Ray exams. Assuming the presence if two transparent layers, it computes two affine velocity fields by minimizing an appropriate objective function with an incremental Gauss-Newton technique. We have designed a realistic simulation scheme of fluoroscopic image sequences to validate our method on data with ground truth and different levels of noise. An experiment on real clinical images is also reported. We then exploit this transparent-motion estimation method to denoise two layers image sequences using a motion-compensated estimation method. In accordance with theory, we show that we reach a denoising factor of 2/3 in a few iterations without bringing any local artifacts in the image sequence.

  3. 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.

  4. A Non-Invasive Imaging Approach to Understanding Speech Changes following Deep Brain Stimulation in Parkinson’s Disease

    PubMed Central

    Narayana, Shalini; Jacks, Adam; Robin, Donald A.; Poizner, Howard; Zhang, Wei; Franklin, Crystal; Liotti, Mario; Vogel, Deanie; Fox, Peter T.

    2009-01-01

    Purpose To explore the use of non-invasive functional imaging and “virtual” lesion techniques to study the neural mechanisms underlying motor speech disorders in Parkinson’s disease. Here, we report the use of Positron Emission Tomography (PET) and transcranial magnetic stimulation (TMS) to explain exacerbated speech impairment following subthalamic nucleus deep brain stimulation (STN-DBS) in a patient with Parkinson’s disease. Method Perceptual and acoustic speech measures as well as cerebral blood flow (CBF) during speech as measured by PET were obtained with STN-DBS on and off. TMS was applied to a region in the speech motor network found to be abnormally active during DBS. Speech disruption by TMS was compared both perceptually and acoustically with that resulting from DBS on. Results Speech production was perceptually inferior and acoustically less contrastive during left STN stimulation compared to no stimulation. Increased neural activity in left dorsal premotor cortex (PMd) was observed during DBS on. “Virtual” lesioning of this region resulted in speech characterized by decreased speech segment duration, increased pause duration, and decreased intelligibility. Conclusions This case report provides evidence that impaired speech production accompanying STN-DBS may be resulting from unintended activation of PMd. Clinical application of functional imaging and TMS may lead to optimizing the delivery of STN-DBS to improve outcomes for speech production as well as general motor abilities. PMID:19029533

  5. Multiparametric Functional MRI: Non-Invasive Imaging of Inflammation and Edema Formation after Kidney Transplantation in Mice

    PubMed Central

    Gutberlet, Marcel; Bräsen, Jan Hinrich; Jang, Mi-Sun; Thorenz, Anja; Chen, Rongjun; Hertel, Barbara; Barrmeyer, Amelie; Schmidbauer, Martina; Meier, Martin; von Vietinghoff, Sibylle; Khalifa, Abedalrazag; Hartung, Dagmar; Haller, Hermann; Wacker, Frank

    2016-01-01

    Background Kidney transplantation (ktx) in mice is used to learn about rejection and to develop new treatment strategies. Past studies have mainly been based on histological or molecular biological methods. Imaging techniques to monitor allograft pathology have rarely been used. Methods Here we investigated mice after isogenic and allogenic ktx over time with functional MRI with diffusion-weighted imaging (DWI) and mapping of T2-relaxation time (T2-mapping) to assess graft inflammation and edema formation. To characterize graft pathology, we used PAS-staining, counted CD3-positive T-lymphocytes, analyzed leukocytes by means flow cytometry. Results DWI revealed progressive restriction of diffusion of water molecules in allogenic kidney grafts. This was paralleled by enhanced infiltration of the kidney by inflammatory cells. Changes in tissue diffusion were not seen following isogenic ktx. T2-times in renal cortex were increased after both isogenic and allogenic transplantation, consistent with tissue edema due to ischemic injury following prolonged cold ischemia time of 60 minutes. Lack of T2 increase in the inner stripe of the inner medulla in allogenic kidney grafts matched loss of tubular autofluorescence and may result from rejection-driven reductions in tubular water content due to tubular dysfunction and renal functional impairment. Conclusions Functional MRI is a valuable non-invasive technique for monitoring inflammation, tissue edema and tubular function. It permits on to differentiate between acute rejection and ischemic renal injury in a mouse model of ktx. PMID:27632553

  6. Non-invasive airway health assessment: Synchrotron imaging reveals effects of rehydrating treatments on mucociliary transit in-vivo

    NASA Astrophysics Data System (ADS)

    Donnelley, Martin; Morgan, Kaye S.; Siu, Karen K. W.; Farrow, Nigel R.; Stahr, Charlene S.; Boucher, Richard C.; Fouras, Andreas; Parsons, David W.

    2014-01-01

    To determine the efficacy of potential cystic fibrosis (CF) therapies we have developed a novel mucociliary transit (MCT) measurement that uses synchrotron phase contrast X-ray imaging (PCXI) to non-invasively measure the transit rate of individual micron-sized particles deposited into the airways of live mice. The aim of this study was to image changes in MCT produced by a rehydrating treatment based on hypertonic saline (HS), a current CF clinical treatment. Live mice received HS containing a long acting epithelial sodium channel blocker (P308); isotonic saline; or no treatment, using a nebuliser integrated within a small-animal ventilator circuit. Marker particle motion was tracked for 20 minutes using PCXI. There were statistically significant increases in MCT in the isotonic and HS-P308 groups. The ability to quantify in vivo changes in MCT may have utility in pre-clinical research studies designed to bring new genetic and pharmaceutical treatments for respiratory diseases into clinical trials.

  7. New imaging technique using degree of polarization for the study of polarimetric properties for non-invasive biomedical diagnostic

    NASA Astrophysics Data System (ADS)

    Buscemi, Isabella C.; Guyot, Steve; Lemoine, Jacques

    2012-06-01

    This research proposes a new imaging technique for near real time multispectral acquisition using CCD RGB cameras of the so called "Degree Of Polarization" (DOP) in polarimetry for future clinical investigation. The aim of exploiting the DOP as the contrast element is to demonstrate that the elliptical DOP provides more information characterizing complex medium than the more traditional linear and circular ones. The system considers an incoherent input white light beam and opportunely calibrated nematic crystals (LCVR), so no mechanical tools are necessary. The particular features of the system indicate it to be the perfect candidate for a new imaging system considering in-vivo (as well as ex-vivo) non invasive superficial diagnostic for medical application as dermatologic diagnostics, since no type of sample preparation is necessary, i.e. tissue biopsy, radiation or contrast agent injection. Thus the biomedical application of this method suggests a simple, direct, fast and also easily exploitable future employment, as a desirable mean for clinical investigation but also for digital recognition in biometrics. Further new elements to improve the model of light scattering and matter-light interaction will be acquired, in particular considering a very complete characterization of the system response using latex microspheres suspension to simulate turbid media with different concentration.

  8. Cardiovascular complications of radiation therapy for thoracic malignancies: the role for non-invasive imaging for detection of cardiovascular disease

    PubMed Central

    Groarke, John D.; Nguyen, Paul L.; Nohria, Anju; Ferrari, Roberto; Cheng, Susan; Moslehi, Javid

    2014-01-01

    Radiation exposure to the thorax is associated with substantial risk for the subsequent development of cardiovascular disease. Thus, the increasing role of radiation therapy in the contemporary treatment of cancer, combined with improving survival rates of patients undergoing this therapy, contributes to a growing population at risk of cardiovascular morbidity and mortality. Associated cardiovascular injuries include pericardial disease, coronary artery disease, valvular disease, conduction disease, cardiomyopathy, and medium and large vessel vasculopathy—any of which can occur at varying intervals following irradiation. Higher radiation doses, younger age at the time of irradiation, longer intervals from the time of radiation, and coexisting cardiovascular risk factors all predispose to these injuries. The true incidence of radiation-related cardiovascular disease remains uncertain due to lack of large multicentre studies with a sufficient duration of cardiovascular follow-up. There are currently no consensus guidelines available to inform the optimal approach to cardiovascular surveillance of recipients of thoracic radiation. Therefore, we review the cardiovascular consequences of radiation therapy and focus on the potential role of non-invasive cardiovascular imaging in the assessment and management of radiation-related cardiovascular disease. In doing so, we highlight characteristics that can be used to identify individuals at risk for developing post-radiation cardiovascular disease and propose an imaging-based algorithm for their clinical surveillance. PMID:23666251

  9. Line-scanning Brillouin microscopy for rapid non-invasive mechanical imaging

    PubMed Central

    Zhang, Jitao; Fiore, Antonio; Yun, Seok-Hyun; Kim, Hanyoup; Scarcelli, Giuliano

    2016-01-01

    Brillouin spectroscopy probes the mechanical properties of material by measuring the optical frequency shift induced by photon-phonon scattering interactions. In traditional configurations, Brillouin spectrometers measure only one point of the sample at a time. This results in long acquisition times for mechanical imaging of large areas. In this work, we demonstrate a parallel detection configuration where the Brillouin shift of hundreds of points in a line can be measured simultaneously. In mm-sized samples, this novel configuration effectively shortens the acquisition time of two-dimensional Brillouin imaging from hours to tens of seconds, thus making it a powerful technology for label-free mechanical characterization of tissue and biomaterials. PMID:27739499

  10. Non-invasive imaging and monitoring cardiotoxicity of cancer therapeutic drugs

    PubMed Central

    Jiji, Ronny S.; Kramer, Christopher M.; Salerno, Michael

    2012-01-01

    Cardiotoxicity due to administration of cancer therapeutic agents such as anthracyclines and herceptin are well described. Established guidelines to screen for chemotherapy-related cardiotoxicity (CRC) are primarily based on serial assessment of left ventricular (LV) ejection fraction (EF). However, other parameters such as LV volume, diastolic function, and strain may also be useful in screening for cardiotoxicity. More recent advances in molecular imaging of apoptosis and tissue characterization by cardiac MRI are techniques which might allow early detection of patients at high risk for developing cardiotoxicity prior to a drop in EF. This comprehensive multi-modality review will discuss both the current established imaging techniques as well as the emerging technologies which may revolutionize the future of screening and evaluation for CRC. PMID:22351492

  11. Non-invasive detection of apoptosis using magnetic resonance imaging and a targeted contrast agent.

    PubMed

    Zhao, M; Beauregard, D A; Loizou, L; Davletov, B; Brindle, K M

    2001-11-01

    The C2 domain of synaptotagmin I, which binds to anionic phospholipids in cell membranes, was shown to bind to the plasma membrane of apoptotic cells by both flow cytometry and confocal microscopy. Conjugation of the protein to superparamagnetic iron oxide nanoparticles allowed detection of this binding using magnetic resonance imaging. Detection of apoptotic cells, using this novel contrast agent, was demonstrated both in vitro, with isolated apoptotic tumor cells, and in vivo, in a tumor treated with chemotherapeutic drugs.

  12. Non-Invasive Detection of Axiliary Nodes by Contrast Enhanced Magnetic Resonance Imaging.

    DTIC Science & Technology

    1996-08-01

    were injected with FreundOs adjuvant to induce an inflammatory response in popliteal lymph nodes and similarly imaged. Conventional spin echo (CSE... lymph nodes to grow, or when they did grow they were small, < 2 mm). Thus the second year of the project focused on the study proposed for the...ratios (CNR) relative to muscle were calculated for each sequence and histopathologic correlation was obtained for all lymph nodes . Findings

  13. Non-invasive terahertz imaging of tissue water content for flap viability assessment

    PubMed Central

    Bajwa, Neha; Au, Joshua; Jarrahy, Reza; Sung, Shijun; Fishbein, Michael C.; Riopelle, David; Ennis, Daniel B.; Aghaloo, Tara; St. John, Maie A.; Grundfest, Warren S.; Taylor, Zachary D.

    2016-01-01

    Accurate and early prediction of tissue viability is the most significant determinant of tissue flap survival in reconstructive surgery. Perturbation in tissue water content (TWC) is a generic component of the tissue response to such surgeries, and, therefore, may be an important diagnostic target for assessing the extent of flap viability in vivo. We have previously shown that reflective terahertz (THz) imaging, a non-ionizing technique, can generate spatially resolved maps of TWC in superficial soft tissues, such as cornea and wounds, on the order of minutes. Herein, we report the first in vivo pilot study to investigate the utility of reflective THz TWC imaging for early assessment of skin flap viability. We obtained longitudinal visible and reflective THz imagery comparing 3 bipedicled flaps (i.e. survival model) and 3 fully excised flaps (i.e. failure model) in the dorsal skin of rats over a postoperative period of 7 days. While visual differences between both models manifested 48 hr after surgery, statistically significant (p < 0.05, independent t-test) local differences in TWC contrast were evident in THz flap image sets as early as 24 hr. Excised flaps, histologically confirmed as necrotic, demonstrated a significant, yet localized, reduction in TWC in the flap region compared to non-traumatized skin. In contrast, bipedicled flaps, histologically verified as viable, displayed mostly uniform, unperturbed TWC across the flap tissue. These results indicate the practical potential of THz TWC sensing to accurately predict flap failure 24 hours earlier than clinical examination. PMID:28101431

  14. Biodegradable Nitrogen-Doped Carbon Nanodots for Non-Invasive Photoacoustic Imaging and Photothermal Therapy

    PubMed Central

    Lee, Changho; Kwon, Woosung; Beack, Songeun; Lee, Donghyun; Park, Yoonsang; Kim, Hyemin; Hahn, Sei Kwang; Rhee, Shi-Woo; Kim, Chulhong

    2016-01-01

    Multifunctional nanoparticles have been widely investigated for biomedical applications, such as imaging, therapy, and drug delivery. Especially, photoactive nanoparticles have received great attention as theranostic agents because of their heat-generating abilities after exposure to laser irradiation. However, photostability and safety issues have been the technical hurdles for further clinical applications. Here, we designed nitrogen (N)-doped carbon nanodots (N-CNDs) that have strong absorption in the near-infrared region, high photostability, and excellent biodegradability. Optimized N-CNDs can be utilized not only as a new photoacoustic (PA) imaging agent but also as a superior photothermal therapy (PTT) agent in vivo because of their strong optical absorption at a specific wavelength. We used N-CNDs to perform in vivo/ex vivo noninvasive PA imaging of sentinel lymph nodes via local delivery and performed PTT for cancer ablation therapy. Finally, biodegradation and renal clearance were confirmed by performing whole-body PA monitoring and a degradation test. PMID:27924157

  15. Non-invasive imaging of breast cancer: synthesis and study of novel near-infrared fluorescent estrogen conjugate

    NASA Astrophysics Data System (ADS)

    Jose, Iven; Vishnoi, Gargi; Deodhar, Kodand; Desai, Uday

    2005-04-01

    The use of near-infrared (NIR) spectroscopy to interrogate deeper tissue volume has shown enormous potential for molecular-based non-invasive imaging when coupled with appropriate excitable dyes. As most of the breast cancers are hormone dependent hence determination of the hormonal receptor status gains paramount importance when deciding the treatment regime for the patient. Since proliferations of the breast cancer cells are often driven by estrogen, we focus on to developing a technique to detect estrogen receptor status. As a first step, the objective of this work was to synthesize and characterize one such novel NIR fluorescent (NIRF) conjugate, which could potentially be used to detect estrogen receptors. The conjugate was synthesized by ester formation between 17-b estradiol and a cyanine dye namely: bis-1, 1-(4-sulfobutyl) indotricarbocyanine-5-carboxylic acid, sodium salt. The cyanine dye is a hydrophilic derivative of indocyanine green (ICG). The ester formed was found to have an extra binding ability with the receptor cites as compared to ICG, which was established by the partition coefficient studies. This cyanine dye has a partition coefficient less than 0.005 as compared to that of ICG (>200)[1]. In addition the ester showed enhanced fluorescent quantum yield than ICG. The replacement of the sodium ion in the ester by a larger glucosammonium ion was found to enhance the hydrophilicity and reduce the toxic effect on the cell lines. The excitation and emission peaks for the conjugate were recorded in the NIR region as 750nm and 788nm respectively. The ester developed was tested on the breast cancer cell lines MCF-7 and found non-toxic. The tagging characteristics were pivotal determinants underlying the ability of the fluorescent conjugate in binding the estrogen receptor of the breast cancer cells. This technique offers the potential of non-invasive detection of hormone receptor status in vivo and may help in decreasing the load of unnecessary biopsies

  16. Non-invasive optical imaging of tumor growth in intact animals

    NASA Astrophysics Data System (ADS)

    Lu, Jinling; Li, Pengcheng; Luo, Qingming; Zhu, Dan

    2003-12-01

    We describe here a system for rapidly visualizing tumor growth in intact rodent mice that is simple, rapid, and eminently accessible and repeatable. We have established new rodent tumor cell line -- SP2/0-GFP cells that stably express high level of green fluorescent protein (GFP) by transfected with a plasmid that encoded GFP using electroporation and selected with G418 for 3 weeks. 1 x 104 - 1x107 SP2/0-GFP mouse melanoma cells were injected s.c. in the ears and legs of 6- to 7-week-old syngeneic male BALB/c mice, and optical images visualized real-time the engrafted tumor growth. The tumor burden was monitored over time by cryogenically cooled charge coupled device (CCD) camera focused through a stereo microscope. The results show that the fluorescence intensity of GFP-expressing tumor is comparably with the tumor growth and/or depress. This in vivo optical imaging based on GFP is sensitive, external, and noninvasive. It affords continuous visual monitoring of malignant growth within intact animals, and may comprise an ideal tool for evaluating antineoplastic therapies.

  17. Contrast changes in fluoroscopic imaging systems and statistical variations of these changes

    NASA Technical Reports Server (NTRS)

    Bailey, N. A.

    1973-01-01

    Experimental studies have indicated that: (1) The response of digitized fluoroscopic imaging systems is linear systems is linear with contrast over a rather wide range of absorber and cavity thicknesses. (2) Contrast changes associated with the addition of aluminum, iodine containing contrast agents and air of thicknesses 1mm or less can be detected with a 95% confidence level. (3) The standard deviation associated with such determination using clinically available X-ray generators and video disc recording is less than 1 percent. A large flat screen X-ray image intensifier has been constructed and some preliminary results obtained. Sensitivity achieved makes dose reduction a factor often greater than previously reported for a system using a conventional X-ray image intensifier.

  18. Non-invasive analysis of root-soil interaction using three complementary imaging approaches

    NASA Astrophysics Data System (ADS)

    Haber-Pohlmeier, Sabina; Tötzke, Christian; Pohlmeier, Andreas; Rudolph-Mohr, Nicole; Kardjilov, Nikolay; Lehmann, Eberhard; Oswald, Sascha E.

    2016-04-01

    Plant roots are known to modify physical, chemical and biological properties of the rhizosphere, thereby, altering conditions for water and nutrient uptake. We aim for capturing the dynamic processes occurring at the soil-root interface in situ. A combination of neutron (NI), magnetic resonance (MRI) and micro-focus X-ray tomography (CT) is applied to monitor the rhizosphere of young plants grown in sandy soil in cylindrical containers (diameter 3 cm). A novel transportable low field MRI system is operated directly at the neutron facility allowing for combined measurements of the very same sample capturing the same hydro-physiological state. The combination of NI, MRI and CT provides three-dimensional access to the root system in respect to structure and hydraulics of the rhizosphere and the transport of dissolved marker substances. The high spatial resolution of neutron imaging and its sensitivity for water can be exploited for the 3D analysis of the root morphology and detailed mapping of three-dimensional water content at the root soil interface and the surrounding soil. MRI has the potential to yield complementary information about the mobility of water, which can be bound in small pores or in the polymeric network of root exudates (mucilage layer). We inject combined tracers (GdDPTA or D2O) to study water fluxes through soil, rhizosphere and roots. Additional CT measurements reveal mechanical impacts of roots on the local microstructure of soil, e.g. showing soil compaction or the formation of cracks. We co-register the NT, MRI and CT data to integrate the complementary information into an aligned 3D data set. This allows, e.g., for co-localization of compacted soil regions or cracks with the specific local soil hydraulics, which is needed to distinguish the contribution of root exudation from mechanical impacts when interpreting altered hydraulic properties of the rhizosphere. Differences between rhizosphere and bulk soil can be detected and interpreted in

  19. Non-invasive deep tissue imaging of iodine modified poly(caprolactone-co-1-4-oxepan-1,5-dione) using X-ray.

    PubMed

    Olsen, Timothy R; Davis, Lundy L; Nicolau, Samantha E; Duncan, Caroline C; Whitehead, Daniel C; Van Horn, Brooke A; Alexis, Frank

    2015-07-01

    When biodegradable polyester devices, like sutures and screws, are implanted into the body, it is very challenging to image them in deep tissue, monitor their degradation, and detect defects. We report our recent findings on non-invasive deep tissue imaging of polyester degradation, stability and integrity using an iodinated-polycaprolactone (i-P(CLcoOPD)) X-ray imaging contrast agent. The results of experiments performed with i-P(CLcoOPD) demonstrate the feasibility to quantify in-situ polyester degradation in vitro and in vivo using rats. We also demonstrate that X-ray imaging could be used to identify and quantify physical defects, such as cracks, in polymeric implants using rabbit animal models. This approach enables non-invasive monitoring of polyester materials and is expected to become an important technology for improving the imaging of polymers at clinically relevant depths.

  20. Non-invasive imaging of the crystalline structure within a human tooth.

    PubMed

    Egan, Christopher K; Jacques, Simon D M; Di Michiel, Marco; Cai, Biao; Zandbergen, Mathijs W; Lee, Peter D; Beale, Andrew M; Cernik, Robert J

    2013-09-01

    The internal crystalline structure of a human molar tooth has been non-destructively imaged in cross-section using X-ray diffraction computed tomography. Diffraction signals from high-energy X-rays which have large attenuation lengths for hard biomaterials have been collected in a transmission geometry. Coupling this with a computed tomography data acquisition and mathematically reconstructing their spatial origins, diffraction patterns from every voxel within the tooth can be obtained. Using this method we have observed the spatial variations of some key material parameters including nanocrystallite size, organic content, lattice parameters, crystallographic preferred orientation and degree of orientation. We have also made a link between the spatial variations of the unit cell lattice parameters and the chemical make-up of the tooth. In addition, we have determined how the onset of tooth decay occurs through clear amorphization of the hydroxyapatite crystal, and we have been able to map the extent of decay within the tooth. The described method has strong prospects for non-destructive probing of mineralized biomaterials.

  1. Non invasive blood flow assessment in diabetic foot ulcer using laser speckle contrast imaging technique

    NASA Astrophysics Data System (ADS)

    Jayanthy, A. K.; Sujatha, N.; Reddy, M. Ramasubba; Narayanamoorthy, V. B.

    2014-03-01

    Measuring microcirculatory tissue blood perfusion is of interest for both clinicians and researchers in a wide range of applications and can provide essential information of the progress of treatment of certain diseases which causes either an increased or decreased blood flow. Diabetic ulcer associated with alterations in tissue blood flow is the most common cause of non-traumatic lower extremity amputations. A technique which can detect the onset of ulcer and provide essential information on the progress of the treatment of ulcer would be of great help to the clinicians. A noninvasive, noncontact and whole field laser speckle contrast imaging (LSCI) technique has been described in this paper which is used to assess the changes in blood flow in diabetic ulcer affected areas of the foot. The blood flow assessment at the wound site can provide critical information on the efficiency and progress of the treatment given to the diabetic ulcer subjects. The technique may also potentially fulfill a significant need in diabetic foot ulcer screening and management.

  2. Thermal fluctuation based study of aqueous deficient dry eyes by non-invasive thermal imaging.

    PubMed

    Azharuddin, Mohammad; Bera, Sumanta Kr; Datta, Himadri; Dasgupta, Anjan Kr

    2014-03-01

    In this paper we have studied the thermal fluctuation patterns occurring at the ocular surface of the left and right eyes for aqueous deficient dry eye (ADDE) patients and control subjects by thermal imaging. We conducted our experiment on 42 patients (84 eyes) with aqueous deficient dry eyes and compared with 36 healthy volunteers (72 eyes) without any history of ocular surface disorder. Schirmer's test, Tear Break-up Time, tear Meniscus height and fluorescein staining tests were conducted. Ocular surface temperature measurement was done, using an FL-IR thermal camera and thermal fluctuation in left and right eyes was calculated and analyzed using MATLAB. The time series containing the sum of squares of the temperature fluctuation on the ocular surface were compared for aqueous deficient dry eye and control subjects. Significant statistical difference between the fluctuation patterns for control and ADDE was observed (p < 0.001 at 95% confidence interval). Thermal fluctuations in left and right eyes are significantly correlated in controls but not in ADDE subjects. The possible origin of such correlation in control and lack of correlation in the ADDE subjects is discussed in the text.

  3. High-resolution non-invasive 3D imaging of paint microstructure by synchrotron-based X-ray laminography

    NASA Astrophysics Data System (ADS)

    Reischig, Péter; Helfen, Lukas; Wallert, Arie; Baumbach, Tilo; Dik, Joris

    2013-06-01

    The characterisation of the microstructure and micromechanical behaviour of paint is key to a range of problems related to the conservation or technical art history of paintings. Synchrotron-based X-ray laminography is demonstrated in this paper to image the local sub-surface microstructure in paintings in a non-invasive and non-destructive way. Based on absorption and phase contrast, the method can provide high-resolution 3D maps of the paint stratigraphy, including the substrate, and visualise small features, such as pigment particles, voids, cracks, wood cells, canvas fibres etc. Reconstructions may be indicative of local density or chemical composition due to increased attenuation of X-rays by elements of higher atomic number. The paint layers and their interfaces can be distinguished via variations in morphology or composition. Results of feasibility tests on a painting mockup (oak panel, chalk ground, vermilion and lead white paint) are shown, where lateral and depth resolution of up to a few micrometres is demonstrated. The method is well adapted to study the temporal evolution of the stratigraphy in test specimens and offers an alternative to destructive sampling of original works of art.

  4. High-Resolution, Non-Invasive Imaging of Upper Vocal Tract Articulators Compatible with Human Brain Recordings

    PubMed Central

    Anumanchipalli, Gopala K.; Dichter, Benjamin; Chaisanguanthum, Kris S.; Johnson, Keith; Chang, Edward F.

    2016-01-01

    A complete neurobiological understanding of speech motor control requires determination of the relationship between simultaneously recorded neural activity and the kinematics of the lips, jaw, tongue, and larynx. Many speech articulators are internal to the vocal tract, and therefore simultaneously tracking the kinematics of all articulators is nontrivial—especially in the context of human electrophysiology recordings. Here, we describe a noninvasive, multi-modal imaging system to monitor vocal tract kinematics, demonstrate this system in six speakers during production of nine American English vowels, and provide new analysis of such data. Classification and regression analysis revealed considerable variability in the articulator-to-acoustic relationship across speakers. Non-negative matrix factorization extracted basis sets capturing vocal tract shapes allowing for higher vowel classification accuracy than traditional methods. Statistical speech synthesis generated speech from vocal tract measurements, and we demonstrate perceptual identification. We demonstrate the capacity to predict lip kinematics from ventral sensorimotor cortical activity. These results demonstrate a multi-modal system to non-invasively monitor articulator kinematics during speech production, describe novel analytic methods for relating kinematic data to speech acoustics, and provide the first decoding of speech kinematics from electrocorticography. These advances will be critical for understanding the cortical basis of speech production and the creation of vocal prosthetics. PMID:27019106

  5. Continuing Education Course #1: Non-Invasive Imaging as a Problem-Solving Tool and Translational Biomarker Strategy in Toxicologic Pathology

    PubMed Central

    Peterson, Richard A.; Gabrielson, Kathy L.; Johnson, G. Allan; Pomper, Martin G.; Coatney, Robert W.; Winkelmann, Christopher T.

    2012-01-01

    The continuing education course “Non-Invasive Imaging as a Problem-Solving Tool and Translational Biomarker Strategy in Toxicologic Pathology” provided a thorough overview of commonly used imaging modalities and the logistics required for integration of small animal imaging into toxicologic pathology. Non-invasive imaging (NIN) is gaining acceptance as an important modality in toxicologic pathology. This technology allows non-terminal, time-course evaluation of functional and morphologic endpoints and can be used to translate biomarkers between preclinical animal models and human patients. Non-invasive imaging can support drug development as well as basic research in academic or industrial environments. An initial overview of theoretical principles was followed by focused presentations on magnetic resonance imaging (MRI)/magnetic resonance microscopy (MRM), positron emission tomography (PET)/single proton emission computed tomography (SPECT), ultrasonography (US, primarily focused on echocardiography), optical (bioluminescent) imaging, and computed tomography (CT). The choice of imaging modality will depend on the research question and the needed resolution. PMID:21147931

  6. On non-invasive 2D and 3D Chromatic White Light image sensors for age determination of latent fingerprints.

    PubMed

    Merkel, Ronny; Gruhn, Stefan; Dittmann, Jana; Vielhauer, Claus; Bräutigam, Anja

    2012-10-10

    The feasibility of 2D-intensity and 3D-topography images from a non-invasive Chromatic White Light (CWL) sensor for the age determination of latent fingerprints is investigated. The proposed method might provide the means to solve the so far unresolved issue of determining a fingerprints age in forensics. Conducting numerous experiments for an indoor crime scene using selected surfaces, different influences on the aging of fingerprints are investigated and the resulting aging variability is determined in terms of inter-person, intra-person, inter-finger and intra-finger variation. Main influence factors are shown to be the sweat composition, temperature, humidity, wind, UV-radiation, surface type, contamination of the finger with water-containing substances, resolution and measured area size, whereas contact time, contact pressure and smearing of the print seem to be of minor importance. Such influences lead to a certain experimental variability in inter-person and intra-person variation, which is higher than the inter-finger and intra-finger variation. Comparing the aging behavior of 17 different features using 1490 time series with a total of 41,520 fingerprint images, the great potential of the CWL technique in combination with the binary pixel feature from prior work is shown. Performing three different experiments for the classification of fingerprints into the two time classes [0, 5 h] and [5, 24 h], a maximum classification performance of 79.29% (kappa=0.46) is achieved for a general case, which is further improved for special cases. The statistical significance of the two best-performing features (both binary pixel versions based on 2D-intensity images) is manually shown and a feature fusion is performed, highlighting the strong dependency of the features on each other. It is concluded that such method might be combined with additional capturing devices, such as microscopes or spectroscopes, to a very promising age estimation scheme.

  7. Assessment of disease activity in patients with rheumatoid arthritis using optical spectral transmission measurements, a non-invasive imaging technique

    PubMed Central

    van Onna, M; Ten Cate, D F; Tsoi, K L; Meier, A J L; Jacobs, J W G; Westgeest, A A A; Meijer, P B L; van Beek, M C; Rensen, W H J; Bijlsma, J W J

    2016-01-01

    Objectives In rheumatoid arthritis (RA), treat-to-target strategies require instruments for valid detection of joint inflammation. Therefore, imaging modalities are increasingly used in clinical practice. Optical spectral transmission (OST) measurements are non-invasive and fast and may therefore have benefits over existing imaging modalities. We tested whether OST could measure disease activity validly in patients with RA. Methods In 59 patients with RA and 10 patients with arthralgia, OST, joint counts, Disease Activity Score (DAS) 28 and ultrasonography (US) were performed. Additionally, MRI was performed in patients with DAS28<2.6. We developed and validated within the same cohort an algorithm for detection of joint inflammation by OST with US as reference. Results At the joint level, OST and US performed similarly inproximal interphalangeal-joints (area under the receiver-operating curve (AUC) of 0.79, p<0.0001) andmetacarpophalangeal joints (AUC 0.78, p<0.0001). Performance was less similar in wrists (AUC 0.62, p=0.006). On the patient level, OST correlated moderately with clinical examination (DAS28 r=0.42, p=0.001), and US scores (r=0.64, p<0.0001). Furthermore, in patients with subclinical and low disease activity, there was a correlation between OST and MRI synovitis score (RAMRIS (Rheumatoid Arthritis MRI Scoring) synovitis), r=0.52, p=0.005. Conclusions In this pilot study, OST performed moderately in the detection of joint inflammation in patients with RA. Further studies are needed to determine the diagnostic performance in a new cohort of patients with RA. PMID:26452538

  8. Utility of spatial frequency domain imaging (SFDI) and laser speckle imaging (LSI) to non-invasively diagnose burn depth in a porcine model☆

    PubMed Central

    Burmeister, David M.; Ponticorvo, Adrien; Yang, Bruce; Becerra, Sandra C.; Choi, Bernard; Durkin, Anthony J.; Christy, Robert J.

    2015-01-01

    Surgical intervention of second degree burns is often delayed because of the difficulty in visual diagnosis, which increases the risk of scarring and infection. Non-invasive metrics have shown promise in accurately assessing burn depth. Here, we examine the use of spatial frequency domain imaging (SFDI) and laser speckle imaging (LSI) for predicting burn depth. Contact burn wounds of increasing severity were created on the dorsum of a Yorkshire pig, and wounds were imaged with SFDI/LSI starting immediately after-burn and then daily for the next 4 days. In addition, on each day the burn wounds were biopsied for histological analysis of burn depth, defined by collagen coagulation, apoptosis, and adnexal/vascular necrosis. Histological results show that collagen coagulation progressed from day 0 to day 1, and then stabilized. Results of burn wound imaging using non-invasive techniques were able to produce metrics that correlate to different predictors of burn depth. Collagen coagulation and apoptosis correlated with SFDI scattering coefficient parameter ( μs′) and adnexal/vascular necrosis on the day of burn correlated with blood flow determined by LSI. Therefore, incorporation of SFDI scattering coefficient and blood flow determined by LSI may provide an algorithm for accurate assessment of the severity of burn wounds in real time. PMID:26138371

  9. Utility of spatial frequency domain imaging (SFDI) and laser speckle imaging (LSI) to non-invasively diagnose burn depth in a porcine model.

    PubMed

    Burmeister, David M; Ponticorvo, Adrien; Yang, Bruce; Becerra, Sandra C; Choi, Bernard; Durkin, Anthony J; Christy, Robert J

    2015-09-01

    Surgical intervention of second degree burns is often delayed because of the difficulty in visual diagnosis, which increases the risk of scarring and infection. Non-invasive metrics have shown promise in accurately assessing burn depth. Here, we examine the use of spatial frequency domain imaging (SFDI) and laser speckle imaging (LSI) for predicting burn depth. Contact burn wounds of increasing severity were created on the dorsum of a Yorkshire pig, and wounds were imaged with SFDI/LSI starting immediately after-burn and then daily for the next 4 days. In addition, on each day the burn wounds were biopsied for histological analysis of burn depth, defined by collagen coagulation, apoptosis, and adnexal/vascular necrosis. Histological results show that collagen coagulation progressed from day 0 to day 1, and then stabilized. Results of burn wound imaging using non-invasive techniques were able to produce metrics that correlate to different predictors of burn depth. Collagen coagulation and apoptosis correlated with SFDI scattering coefficient parameter [Formula: see text] and adnexal/vascular necrosis on the day of burn correlated with blood flow determined by LSI. Therefore, incorporation of SFDI scattering coefficient and blood flow determined by LSI may provide an algorithm for accurate assessment of the severity of burn wounds in real time.

  10. Accurate 3D kinematic measurement of temporomandibular joint using X-ray fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Yamazaki, Takaharu; Matsumoto, Akiko; Sugamoto, Kazuomi; Matsumoto, Ken; Kakimoto, Naoya; Yura, Yoshiaki

    2014-04-01

    Accurate measurement and analysis of 3D kinematics of temporomandibular joint (TMJ) is very important for assisting clinical diagnosis and treatment of prosthodontics and orthodontics, and oral surgery. This study presents a new 3D kinematic measurement technique of the TMJ using X-ray fluoroscopic images, which can easily obtain the TMJ kinematic data in natural motion. In vivo kinematics of the TMJ (maxilla and mandibular bone) is determined using a feature-based 2D/3D registration, which uses beads silhouette on fluoroscopic images and 3D surface bone models with beads. The 3D surface models of maxilla and mandibular bone with beads were created from CT scans data of the subject using the mouthpiece with the seven strategically placed beads. In order to validate the accuracy of pose estimation for the maxilla and mandibular bone, computer simulation test was performed using five patterns of synthetic tantalum beads silhouette images. In the clinical applications, dynamic movement during jaw opening and closing was conducted, and the relative pose of the mandibular bone with respect to the maxilla bone was determined. The results of computer simulation test showed that the root mean square errors were sufficiently smaller than 1.0 mm and 1.0 degree. In the results of clinical application, during jaw opening from 0.0 to 36.8 degree of rotation, mandibular condyle exhibited 19.8 mm of anterior sliding relative to maxillary articular fossa, and these measurement values were clinically similar to the previous reports. Consequently, present technique was thought to be suitable for the 3D TMJ kinematic analysis.

  11. Ultrasound imaging of apoptosis: high-resolution non-invasive monitoring of programmed cell death in vitro, in situ and in vivo

    PubMed Central

    Czarnota, G J; Kolios, M C; Abraham, J; Portnoy, M; Ottensmeyer, F P; Hunt, J W; Sherar, M D

    1999-01-01

    A new non-invasive method for monitoring apoptosis has been developed using high frequency (40 MHz) ultrasound imaging. Conventional ultrasound backscatter imaging techniques were used to observe apoptosis occurring in response to anticancer agents in cells in vitro, in tissues ex vivo and in live animals. The mechanism behind this ultrasonic detection was identified experimentally to be the subcellular nuclear changes, condensation followed by fragmentation, that cells undergo during apoptosis. These changes dramatically increase the high frequency ultrasound scattering efficiency of apoptotic cells over normal cells (25- to 50-fold change in intensity). The result is that areas of tissue undergoing apoptosis become much brighter in comparison to surrounding viable tissues. The results provide a framework for the possibility of using high frequency ultrasound imaging in the future to non-invasively monitor the effects of chemotherapeutic agents and other anticancer treatments in experimental animal systems and in patients. © 1999 Cancer Research Campaign PMID:10507779

  12. New Imaging Methods for Non-invasive Assessment of Mechanical, Structural, and Biochemical Properties of Human Achilles Tendon: A Mini Review

    PubMed Central

    Fouré, Alexandre

    2016-01-01

    The mechanical properties of tendon play a fundamental role to passively transmit forces from muscle to bone, withstand sudden stretches, and act as a mechanical buffer allowing the muscle to work more efficiently. The use of non-invasive imaging methods for the assessment of human tendon's mechanical, structural, and biochemical properties in vivo is relatively young in sports medicine, clinical practice, and basic science. Non-invasive assessment of the tendon properties may enhance the diagnosis of tendon injury and the characterization of recovery treatments. While ultrasonographic imaging is the most popular tool to assess the tendon's structural and indirectly, mechanical properties, ultrasonographic elastography, and ultra-high field magnetic resonance imaging (UHF MRI) have recently emerged as potentially powerful techniques to explore tendon tissues. This paper highlights some methodological cautions associated with conventional ultrasonography and perspectives for in vivo human Achilles tendon assessment using ultrasonographic elastography and UHF MRI. PMID:27512376

  13. Reproducibility of Non-Invasive Assessment of Skin Endothelial Function Using Laser Doppler Flowmetry and Laser Speckle Contrast Imaging

    PubMed Central

    Puissant, Cyril; Abraham, Pierre; Durand, Sylvain; Humeau-Heurtier, Anne; Faure, Sébastien; Lefthériotis, Georges; Rousseau, Pascal; Mahé, Guillaume

    2013-01-01

    Background Endothelial dysfunction precedes atherosclerosis. Vasodilation induced by acetylcholine (ACh) is a specific test of endothelial function. Reproducibility of laser techniques such as laser-Doppler-flowmetry (LDF) and Laser-speckle-contrast-imaging (LSCI) to detect ACh vasodilation is debated and results expressions lack standardization. We aimed to study at a 7-day interval (i) the inter-subject reproducibility, (ii) the intra-subjects reproducibility, and (iii) the effect of the results expressions over variability. Methods and Results Using LDF and LSCI simultaneously, we performed two different ACh-iontophoresis protocols. The maximal ACh vasodilation (peak-ACh) was expressed as absolute or normalized flow or conductance values. Inter-subject reproducibility was expressed as coefficient of variation (inter-CV,%). Intra-subject reproducibility was expressed as within subject coefficients of variation (intra-CV,%), and intra-class correlation coefficients (ICC). Fifteen healthy subjects were included. The inter-subject reproducibility of peak-ACh depended upon the expression of the results and ranged from 55% to 162% for LDF and from 17% to 83% for LSCI. The intra-subject reproducibility (intra-CV/ICC) of peak-ACh was reduced when assessed with LSCI compared to LDF no matter how the results were expressed and whatever the protocol used. The highest intra-subject reproducibility was found using LSCI. It was 18.7%/0.87 for a single current stimulation (expressed as cutaneous vascular conductance) and 11.4%/0.61 for multiple current stimulations (expressed as absolute value). Conclusion ACh-iontophoresis coupled with LSCI is a promising test to assess endothelial function because it is reproducible, safe, and non-invasive. N°: NCT01664572. PMID:23620742

  14. Non-invasive determination of left ventricular workload in patients with aortic stenosis using magnetic resonance imaging and Doppler echocardiography.

    PubMed

    Keshavarz-Motamed, Zahra; Garcia, Julio; Gaillard, Emmanuel; Capoulade, Romain; Le Ven, Florent; Cloutier, Guy; Kadem, Lyes; Pibarot, Philippe

    2014-01-01

    Early detection and accurate estimation of aortic stenosis (AS) severity are the most important predictors of successful long-term outcomes in patients. Current clinical parameters used for evaluation of the AS severity have several limitations including flow dependency. Estimation of AS severity is specifically challenging in patients with low-flow and low transvalvular pressure gradient conditions. A proper diagnosis in these patients needs a comprehensive evaluation of the left ventricle (LV) hemodynamic loads. This study has two objectives: (1) developing a lumped-parameter model to describe the ventricular-valvular-arterial interaction and to estimate the LV stroke work (SW); (2) introducing and validating a new index, the normalized stroke work (N-SW), to assess the global hemodynamic load imposed on the LV. N-SW represents the global hemodynamic load that the LV faces for each unit volume of blood ejected. The model uses a limited number of parameters which all can be measured non-invasively using current clinical imaging modalities. The model was first validated by comparing its calculated flow waveforms with the ones measured using Cardiovascular Magnetic Resonance (CMR) in 49 patients and 8 controls. A very good correlation and concordance were found throughout the cycle (median root mean square: 12.21 mL/s) and between the peak values (r = 0.98; SEE = 0.001, p<0.001). The model was then used to determine SW using the parameters measured with transthoracic Doppler-echocardiography (TTE) and CMR. N-SW showed very good correlations with a previously-validated index of global hemodynamic load, the valvular arterial impedance ([Formula: see text]), using data from both imaging modalities (TTE: r = 0.82, SEE = 0.01, p<0.001; CMR: r = 0.74, SEE = 0.01, p<0.001). Furthermore, unlike , N-SW was almost independent from variations in the flow rate. This study suggests that considering N-SW may provide incremental diagnostic and prognostic information, beyond what

  15. High-Resolution Harmonics Ultrasound Imaging for Non-Invasive Characterization of Wound Healing in a Pre-Clinical Swine Model

    PubMed Central

    Mathew-Steiner, Shomita S.; Dixith, Sriteja; Vanzant, Daniel; Kim, Jayne; Dickerson, Jennifer L.; Datta, Soma; Powell, Heather; Roy, Sashwati; Bergdall, Valerie; Sen, Chandan K.

    2015-01-01

    This work represents the first study employing non-invasive high-resolution harmonic ultrasound imaging to longitudinally characterize skin wound healing. Burn wounds (day 0-42), on the dorsum of a domestic Yorkshire white pig were studied non-invasively using tandem digital planimetry, laser speckle imaging and dual mode (B and Doppler) ultrasound imaging. Wound depth, as measured by B-mode imaging, progressively increased until day 21 and decreased thereafter. Initially, blood flow at the wound edge increased up to day 14 and subsequently regressed to baseline levels by day 21, when the wound was more than 90% closed. Coinciding with regression of blood flow at the wound edge, there was an increase in blood flow in the wound bed. This was observed to regress by day 42. Such changes in wound angiogenesis were corroborated histologically. Gated Doppler imaging quantitated the pulse pressure of the primary feeder artery supplying the wound site. This pulse pressure markedly increased with a bimodal pattern following wounding connecting it to the induction of wound angiogenesis. Finally, ultrasound elastography measured tissue stiffness and visualized growth of new tissue over time. These studies have elegantly captured the physiological sequence of events during the process of wound healing, much of which is anticipated based on certain dynamics in play, to provide the framework for future studies on molecular mechanisms driving these processes. We conclude that the tandem use of non-invasive imaging technologies has the power to provide unprecedented insight into the dynamics of the healing skin tissue. PMID:25799513

  16. Non-Invasive In Vivo Imaging and Quantification of Tumor Growth and Metastasis in Rats Using Cells Expressing Far-Red Fluorescence Protein.

    PubMed

    Christensen, Jon; Vonwil, Daniel; Shastri, V Prasad

    2015-01-01

    Non-invasive in vivo imaging is emerging as an important tool for basic and preclinical research. Near-infrared (NIR) fluorescence dyes and probes have been used for non-invasive optical imaging since in the NIR region absorption and auto fluorescence by body tissue is low, thus permitting for greater penetration depths and high signal to noise ratio. Currently, cell tracking systems rely on labeling cells prior to injection or administering probes targeting the cell population of choice right before imaging. These approaches do not enable imaging of tumor growth, as the cell label is diluted during cell division. In this study we have developed cell lines stably expressing the far-red fluorescence protein E2-Crimson, thus enabling continuous detection and quantification of tumor growth. In a xenograft rat model, we show that E2-Crimson expressing cells can be detected over a 5 week period using optical imaging. Fluorescence intensities correlated with tumor volume and weight and allowed for a reliable and robust quantification of the entire tumor compartment. Using a novel injection regime, the seeding of MDA-MB-231 breast cancer cells in the lungs in a rat model was established and verified.

  17. Non-invasive Assessment of Elastic Modulus of Arterial Constructs during Cell Culture using Ultrasound Elasticity Imaging

    PubMed Central

    Dutta, Debaditya; Lee, Kee-Won; Allen, Robert A.; Wang, Yadong; Brigham, John C.; Kim, Kang

    2013-01-01

    Mechanical strength is a key design factor for engineered arteries. Most existing techniques assess the mechanical property of arterial constructs destructively, leading to a large number of animal sacrifices. We propose an ultrasound-based non-invasive mechanical strength assessment technique for engineered arterial constructs. Tubular scaffolds made from a biodegradable elastomer and seeded with vascular fibroblasts and smooth muscle cells were cultured in a pulsatile-flow bioreactor. Scaffold distension was computed from ultrasound radiofrequency signals of the pulsating scaffold via two-dimensional phase-sensitive speckle tracking. The Young's modulus was then calculated by solving inverse problem from the distension and the recorded pulse pressure. Stiffness thus computed from ultrasound correlated well with direct mechanical testing results. As the scaffolds matured in culture, ultrasound measurements showed increased Young's modulus and histology confirmed the growth of cells and collagen fibrils in the constructs. The results show that ultrasound elastography non-invasively assesses and monitors the mechanical properties of arterial constructs. PMID:23932282

  18. Non-invasive Florentine Renaissance Panel Painting Replica Structures Investigation by Using Terahertz Time-Domain Imaging (THz-TDI) Technique

    NASA Astrophysics Data System (ADS)

    Koch Dandolo, Corinna L.; Picollo, Marcello; Cucci, Costanza; Jepsen, Peter Uhd

    2016-11-01

    The potentials of the Terahertz Time-Domain Imaging (THz-TDI) technique for a non-invasive inspection of panel paintings have been considered in detail. The THz-TD data acquired on a replica of a panel painting made in imitation of Italian Renaissance panel paintings were processed in order to provide insights as to the limits and potentials of the technique in detecting different kinds of underdrawings and paint layers. Constituent layers, construction techniques, and anomalies were identified and localized by interpreting the extracted THz dielectric stratigraphy.

  19. IDH mutation status is associated with a distinct hypoxia/angiogenesis transcriptome signature which is non-invasively predictable with rCBV imaging in human glioma.

    PubMed

    Kickingereder, Philipp; Sahm, Felix; Radbruch, Alexander; Wick, Wolfgang; Heiland, Sabine; Deimling, Andreas von; Bendszus, Martin; Wiestler, Benedikt

    2015-11-05

    The recent identification of IDH mutations in gliomas and several other cancers suggests that this pathway is involved in oncogenesis; however effector functions are complex and yet incompletely understood. To study the regulatory effects of IDH on hypoxia-inducible-factor 1-alpha (HIF1A), a driving force in hypoxia-initiated angiogenesis, we analyzed mRNA expression profiles of 288 glioma patients and show decreased expression of HIF1A targets on a single-gene and pathway level, strong inhibition of upstream regulators such as HIF1A and downstream biological functions such as angio- and vasculogenesis in IDH mutant tumors. Genotype/imaging phenotype correlation analysis with relative cerebral blood volume (rCBV) MRI - a robust and non-invasive estimate of tumor angiogenesis - in 73 treatment-naive patients with low-grade and anaplastic gliomas showed that a one-unit increase in rCBV corresponded to a two-third decrease in the odds for an IDH mutation and correctly predicted IDH mutation status in 88% of patients. Together, these findings (1) show that IDH mutation status is associated with a distinct angiogenesis transcriptome signature which is non-invasively predictable with rCBV imaging and (2) highlight the potential future of radiogenomics (i.e. the correlation between cancer imaging and genomic features) towards a more accurate diagnostic workup of brain tumors.

  20. A Preclinical Evaluation of Antrodia camphorata Alcohol Extracts in the Treatment of Non-Small Cell Lung Cancer Using Non-Invasive Molecular Imaging

    PubMed Central

    Chiou, Jeng-Feng; Wu, Alexander T. H.; Wang, Wei-Tin; Kuo, Tsu-Hsiang; Gelovani, Juri G.; Lin, I-Hsin; Wu, Chih-Hsiung; Chiu, Wen-Ta; Deng, Win-Ping

    2011-01-01

    This study was carried out to provide a platform for the pre-clinical evaluation of anti-cancer properties of a unique CAM (complementary and alternative medicine) agent, Antrodia camphorata alcohol extract (ACAE), in a mouse model with the advantageous non-invasive in vivo bioluminescence molecular imaging technology. In vitro analyses on the proliferation, migration/invasion, cell cycle and apoptosis were performed on ACAE-treated non-small cell lung cancer cells, H441GL and control CGL1 cells. In vivo, immune-deficient mice were inoculated subcutaneously with H441GL followed by oral gavages of ACAE. The effect of ACAE on tumor progression was monitored by non-invasive bioluminescence imaging. The proliferation and migration/invasion of H441GL cells were inhibited by ACAE in a dose-dependent manner. In addition, ACAE induced cell cycle arrest at G0/G1 phase and apoptosis in H441GL cells as shown by flow cytometric analysis, Annexin-V immunoflourescence and DNA fragmentation. In vivo bioluminescence imaging revealed that tumorigenesis was significantly retarded by oral treatment of ACAE in a dose-dependent fashion. Based on our experimental data, ACAE contains anti-cancer properties and could be considered as a potential CAM agent in future clinical evaluation. PMID:21785640

  1. Optimization of multi-image pose recovery of fluoroscope tracking (FTRAC) fiducial in an image-guided femoroplasty system

    NASA Astrophysics Data System (ADS)

    Liu, Wen P.; Armand, Mehran; Otake, Yoshito; Taylor, Russell H.

    2011-03-01

    Percutaneous femoroplasty [1], or femoral bone augmentation, is a prospective alternative treatment for reducing the risk of fracture in patients with severe osteoporosis. We are developing a surgical robotics system that will assist orthopaedic surgeons in planning and performing a patient-specific, augmentation of the femur with bone cement. This collaborative project, sponsored by the National Institutes of Health (NIH), has been the topic of previous publications [2],[3] from our group. This paper presents modifications to the pose recovery of a fluoroscope tracking (FTRAC) fiducial during our process of 2D/3D registration of X-ray intraoperative images to preoperative CT data. We show improved automata of the initial pose estimation as well as lower projection errors with the advent of a multiimage pose optimization step.

  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. A Biocompatible “Split Luciferin” Reaction and its Application for Non-Invasive Bioluminescent Imaging of Protease Activity in Living Animals

    PubMed Central

    Godinat, Aurélien; Budin, Ghyslain; Molares, Alma R.; Park, Hyo Min; Sanman, Laura E.; Bogyo, Matthew; Yu, Allen; Stahl, Andreas; Dubikovskaya, Elena A.

    2014-01-01

    The great complexity of many human pathologies such as cancer, diabetes, and neurodegenerative diseases requires new tools for studies of biological processes on the whole organism level. The discovery of novel biocompatible reactions has tremendously advanced our understanding of basic biology, however, no efficient tools exist for real-time non-invasive imaging of many human proteases that play very important roles in multiple human disorders. We recently reported that “split luciferin” biocompatible reaction represents a valuable tool for evaluation of protease activity directly in living animals using bioluminescence imaging (BLI). Since BLI is the most sensitive in vivo imaging modality known to date, this method can be widely applied for the evaluation of multiple proteases activity as well as identification of their new peptide-specific substrates. In this protocol we describe several applications of this “split luciferin” reaction for quantification of protease activities in test tube assays and living animals. PMID:25205565

  4. Visceral anatomy of ocean sunfish (Mola mola (L., 1758), Molidae, Tetraodontiformes) and angler (Lophius piscatorius (L., 1758), Lophiidae, Lophiiformes) investigated by non-invasive imaging techniques.

    PubMed

    Chanet, Bruno; Guintard, Claude; Boisgard, Thierry; Fusellier, Marion; Tavernier, Cédric; Betti, Eric; Madec, Stéphane; Richaudeau, Yvan; Raphaël, Christian; Dettaï, Agnès; Lecointre, Guillaume

    2012-12-01

    The purpose of this work is to examine the gross visceral anatomy of ocean sunfish and angler using non-invasive imaging techniques: computed tomography imaging (CT) and magnetic resonance imaging (MRI). Similarities and differences in the internal organisation of these two species are verified. Both species lack a swimbladder and present a significant asymmetry in the hepatic lobes, an elongated bile duct terminating close to the stomach, a compact thyroid embedded in a blood lacuna, and very reduced brain and spinal cord. These observations are important in regard to the close relationships between Tetraodontiformes and Lophiiformes, established by several molecular works, but not yet confirmed by morpho-anatomical data. However the occurrence of these features has to be examined in other taxa before phylogenetic hypotheses are proposed.

  5. Detection of DSS-induced gastrointestinal mucositis in mice by non-invasive optical near-infrared (NIR) imaging of cathepsin activity.

    PubMed

    Finnberg, Niklas K; Liu, Yvette; El-Deiry, Wafik S

    2013-08-01

    Approximately 1.4 million people of the US population suffer from Inflammatory Bowel Disease (IBD) of which the most common conditions are ulcerative colitis (UC) and Crohn disease (CD). Colonoscopy and small bowel follow through are considered the current gold standard in diagnosing IBD. However, improved imaging and increased diagnostic sensitivity could be beneficial. Optical molecular imaging has the potential to become a powerful and practical tool for early detection, image-guided biopsy, and surgery in diagnosing and treating patients with IBD. Here we used a well characterized chemical model to initiate experimental IBD in mice by feeding with dextran sulfate sodium (DSS) containing drinking water in an attempt to investigate the utility of non-invasive infrared (NIR) optical imaging in the detection gastrointestinal (GI) injury. We employed a "smart probe" (ProSense680) cleaved and fluorescently activated in the NIR-spectrum by various forms of secreted cathepsins. This probe has previously been shown to serve as a biomarker for the homing of inflammatory cells to injury. Our investigation suggests that NIR optical imaging can detect cathepsin-dependent probe cleavage non-invasively in animals with DSS-induced IBD. Increased tissue probe-retention and fluorescence was associated with increased infiltration of inflammatory cells, epithelial atrophy and sterilization of the mucosa. Furthermore, using NIR-imaging ex vivo we were able to document regional "hot spots" of inflammatory damage to the large intestine suggesting this method potentially could be coupled with colonoscopy investigation to aid in the sampling and the diagnostics of IBD.

  6. MO-E-BRD-03: Intra-Operative Breast Brachytherapy: Is One Stop Shopping Best? [Non-invasive Image-Guided Breast Brachytherapy

    SciTech Connect

    Libby, B.

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  7. Non-invasive, photonics-based diagnostic, imaging, monitoring, and light delivery techniques for the recognition, quantification and treatment of malignant and chronic inflammatory conditions

    NASA Astrophysics Data System (ADS)

    Davies, N.; Davies-Shaw, D.; Shaw, J. D.

    2007-02-01

    We report firsthand on innovative developments in non-invasive, biophotonic techniques for a wide range of diagnostic, imaging and treatment options, including the recognition and quantification of cancerous, pre-cancerous cells and chronic inflammatory conditions. These techniques have benefited from the ability to target the affected site by both monochromatic light and broad multiple wavelength spectra. The employment of such wavelength or color-specific properties embraces the fluorescence stimulation of various photosensitizing drugs, and the instigation and detection of identified fluorescence signatures attendant upon laser induced fluorescence (LIF) phenomena as transmitted and propagated by precancerous, cancerous and normal tissue. In terms of tumor imaging and therapeutic and treatment options, we have exploited the abilities of various wavelengths to penetrate to different depths, through different types of tissues, and have explored quantifiable absorption and reflection characteristics upon which diagnostic assumptions can be reliably based and formulated. These biophotonic-based diagnostic, sensing and imaging techniques have also benefited from, and have been further enhanced by, the integrated ability to provide various power levels to be employed at various stages in the procedure. Applications are myriad, including non-invasive, non destructive diagnosis of in vivo cell characteristics and functions; light-based tissue analysis; real-time monitoring and mapping of brain function and of tumor growth; real time monitoring of the surgical completeness of tumor removal during laser-imaged/guided brain resection; diagnostic procedures based on fluorescence life-time monitoring, the monitoring of chronic inflammatory conditions (including rheumatoid arthritis), and continuous blood glucose monitoring in the control of diabetes.

  8. A simple method for the generation of organ and vessel contours from roentgenographic or fluoroscopic images

    NASA Technical Reports Server (NTRS)

    Newell, J. D.; Keller, R. A.; Baily, N. A.

    1974-01-01

    A simple method for outlining or contouring any area defined by a change in film density or fluoroscopic screen intensity is described. The entire process, except for the positioning of an electronic window, is accomplished using a small computer having appropriate softwave. The electronic window is operator positioned over the area to be processed. The only requirement is that the window be large enough to encompass the total area to be considered.

  9. Using non-invasive magnetic resonance imaging (MRI) to assess the reduction of Cr(VI) using a biofilm-palladium catalyst.

    PubMed

    Beauregard, D A; Yong, P; Macaskie, L E; Johns, M L

    2010-09-01

    Industrial waste streams may contain contaminants that are valuable like Pd(II) and/or toxic and mutagenic like Cr(VI). Using Serratia sp. biofilm the former was biomineralized to produce a supported nanocrystalline Pd(0) catalyst, and this biofilm-Pd heterogeneous catalyst was then used to reduce Cr(VI) to less dangerous Cr(III) at room temperature, with formate as the electron donor. Cr(VI)((aq)) is non-paramagnetic while Cr(III)((aq)) is paramagnetic, which enabled spatial mapping of Cr species concentrations within the reactor cell using non-invasive magnetic resonance (MR) imaging experiments. Spatial reactivity heterogeneities were thus examined. In batch reactions, these could be attributed primarily to heterogeneity of Pd(0) distribution and to the development of gas bubbles within the reactor. In continuous flow reactions, spatial reactivity heterogeneities resulted primarily from heterogeneity of Cr(VI) delivery.

  10. Non-invasive dual fluorescence in vivo imaging for detection of macrophage infiltration and matrix metalloproteinase (MMP) activity in inflammatory arthritic joints.

    PubMed

    Cho, Hongsik; Bhatti, Fazal-Ur-Rehman; Yoon, Tae Won; Hasty, Karen A; Stuart, John M; Yi, Ae-Kyung

    2016-05-01

    Detection and intervention at an early stage is a critical factor to impede arthritis progress. Here we present a non-invasive method to detect inflammatory changes in joints of arthritic mice. Inflammation was monitored by dual fluorescence optical imaging for near-infrared fluorescent (750F) matrix-metalloproteinase activatable agent and allophycocyanin-conjugated anti-mouse CD11b. Increased intensity of allophycocyanin (indication of macrophage accumulation) and 750F (indication of matrix-metalloproteinase activity) showed a biological relationship with the arthritis severity score and the histopathology score of arthritic joints. Our results demonstrate that this method can be used to detect early stages of arthritis with minimum intervention in small animal models.

  11. SU-E-J-01: 3D Fluoroscopic Image Estimation From Patient-Specific 4DCBCT-Based Motion Models

    SciTech Connect

    Dhou, S; Hurwitz, M; Lewis, J; Mishra, P

    2014-06-01

    Purpose: 3D motion modeling derived from 4DCT images, taken days or weeks before treatment, cannot reliably represent patient anatomy on the day of treatment. We develop a method to generate motion models based on 4DCBCT acquired at the time of treatment, and apply the model to estimate 3D time-varying images (referred to as 3D fluoroscopic images). Methods: Motion models are derived through deformable registration between each 4DCBCT phase, and principal component analysis (PCA) on the resulting displacement vector fields. 3D fluoroscopic images are estimated based on cone-beam projections simulating kV treatment imaging. PCA coefficients are optimized iteratively through comparison of these cone-beam projections and projections estimated based on the motion model. Digital phantoms reproducing ten patient motion trajectories, and a physical phantom with regular and irregular motion derived from measured patient trajectories, are used to evaluate the method in terms of tumor localization, and the global voxel intensity difference compared to ground truth. Results: Experiments included: 1) assuming no anatomic or positioning changes between 4DCT and treatment time; and 2) simulating positioning and tumor baseline shifts at the time of treatment compared to 4DCT acquisition. 4DCBCT were reconstructed from the anatomy as seen at treatment time. In case 1) the tumor localization error and the intensity differences in ten patient were smaller using 4DCT-based motion model, possible due to superior image quality. In case 2) the tumor localization error and intensity differences were 2.85 and 0.15 respectively, using 4DCT-based motion models, and 1.17 and 0.10 using 4DCBCT-based models. 4DCBCT performed better due to its ability to reproduce daily anatomical changes. Conclusion: The study showed an advantage of 4DCBCT-based motion models in the context of 3D fluoroscopic images estimation. Positioning and tumor baseline shift uncertainties were mitigated by the 4DCBCT

  12. Application of visible and near infrared hyperspectral imaging for non-invasively measuring distribution of water-holding capacity in salmon flesh.

    PubMed

    Wu, Di; Sun, Da-Wen

    2013-11-15

    Water-holding capacity (WHC) is a primary quality determinant of salmon flesh. One of the limiting factors for not having a direct measurement of WHC for salmon quality grading is that current WHC measurements are destructive, time-consuming, and inefficient. In this study, two hyperspectral image systems operated in the visible and short-wave near infrared range (400-1000 nm) and the long-wave near infrared range (897-1753 nm) were applied for non-invasive determination of four WHC indices, namely percentage liquid loss (PLL), percentage water loss (PWL), percentage fat loss (PFL), and percentage water remained (PWR) of salmon flesh. Two calibration methods of partial least square regression (PLSR) and least-squares support vector machines (LS-SVM) were applied, respectively, to establish calibration models of WHC indices based on the spectral signatures of salmon flesh, and the performances of these two methods were compared to determine the optimal spectral calibration strategy. The performances were also compared between two hyperspectral image systems, when full range spectra were considered. Out of 121 wavelength variables, only thirteen (PLL), twelve (PWL), nine (PFL), and twelve variables (PWR) were selected as important variables by using competitive adaptive reweighted sampling (CARS) algorithm to reduce redundancy and collinearity of hyperspectral images. The CARS-PLSR combination was identified as the optimal method to calibrate the prediction models for WHC determination, resulting in good correlation coefficient of prediction (rP) of 0.941, 0.937, 0.815, and 0.970 for PLL, PWL, PFL, and PWR analysis, respectively. CARS-PLSR equations were obtained according to the regression coefficients of the CARS-PLSR models and were transferred to each pixel in the image for visualizing WHC indices in all portions of the salmon fillet. The overall results show that the laborious, time-consuming, and destructive traditional techniques could be replaced by

  13. Non-invasive Parenchymal, Vascular and Metabolic High-frequency Ultrasound and Photoacoustic Rat Deep Brain Imaging

    PubMed Central

    Giustetto, Pierangela; Filippi, Miriam; Castano, Mauro; Terreno, Enzo

    2015-01-01

    Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central nervous system of small animals. However, transdermal and transcranial neuroimaging is frequently affected by low sensitivity, image aberrations and loss of space resolution, requiring scalp or even skull removal before imaging. To overcome this challenge, a new protocol is presented to gain significant insights in brain hemodynamics by photoacoustic and high-frequency ultrasounds imaging with the animal skin and skull intact. The procedure relies on the passage of ultrasound (US) waves and laser directly through the fissures that are naturally present on the animal cranium. By juxtaposing the imaging transducer device exactly in correspondence to these selected areas where the skull has a reduced thickness or is totally absent, one can acquire high quality deep images and explore internal brain regions that are usually difficult to anatomically or functionally describe without an invasive approach. By applying this experimental procedure, significant data can be collected in both sonic and optoacoustic modalities, enabling to image the parenchymal and the vascular anatomy far below the head surface. Deep brain features such as parenchymal convolutions and fissures separating the lobes were clearly visible. Moreover, the configuration of large and small blood vessels was imaged at several millimeters of depth, and precise information were collected about blood fluxes, vascular stream velocities and the hemoglobin chemical state. This repertoire of data could be crucial in several research contests, ranging from brain vascular disease studies to experimental techniques involving the systemic administration of exogenous chemicals or other objects endowed with imaging contrast enhancement properties. In conclusion, thanks to the presented protocol, the US and PA techniques become an attractive noninvasive

  14. Non-invasive parenchymal, vascular and metabolic high-frequency ultrasound and photoacoustic rat deep brain imaging.

    PubMed

    Giustetto, Pierangela; Filippi, Miriam; Castano, Mauro; Terreno, Enzo

    2015-03-02

    Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central nervous system of small animals. However, transdermal and transcranial neuroimaging is frequently affected by low sensitivity, image aberrations and loss of space resolution, requiring scalp or even skull removal before imaging. To overcome this challenge, a new protocol is presented to gain significant insights in brain hemodynamics by photoacoustic and high-frequency ultrasounds imaging with the animal skin and skull intact. The procedure relies on the passage of ultrasound (US) waves and laser directly through the fissures that are naturally present on the animal cranium. By juxtaposing the imaging transducer device exactly in correspondence to these selected areas where the skull has a reduced thickness or is totally absent, one can acquire high quality deep images and explore internal brain regions that are usually difficult to anatomically or functionally describe without an invasive approach. By applying this experimental procedure, significant data can be collected in both sonic and optoacoustic modalities, enabling to image the parenchymal and the vascular anatomy far below the head surface. Deep brain features such as parenchymal convolutions and fissures separating the lobes were clearly visible. Moreover, the configuration of large and small blood vessels was imaged at several millimeters of depth, and precise information were collected about blood fluxes, vascular stream velocities and the hemoglobin chemical state. This repertoire of data could be crucial in several research contests, ranging from brain vascular disease studies to experimental techniques involving the systemic administration of exogenous chemicals or other objects endowed with imaging contrast enhancement properties. In conclusion, thanks to the presented protocol, the US and PA techniques become an attractive noninvasive

  15. Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection

    PubMed Central

    Mobashsher, A. T.; Bialkowski, K. S.; Abbosh, A. M.; Crozier, S.

    2016-01-01

    An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm3. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage’s depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates its feasibility

  16. Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection.

    PubMed

    Mobashsher, A T; Bialkowski, K S; Abbosh, A M; Crozier, S

    2016-01-01

    An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm3. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage's depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates its feasibility for

  17. Non-invasive identification of traditional red lake pigments in fourteenth to sixteenth centuries paintings through the use of hyperspectral imaging technique

    NASA Astrophysics Data System (ADS)

    Vitorino, T.; Casini, A.; Cucci, C.; Melo, M. J.; Picollo, M.; Stefani, L.

    2015-11-01

    The present paper, which focuses on the identification of red lake pigments, in particular madder, brazilwood, and cochineal, addresses the advantages and drawbacks of using reflectance hyperspectral imaging in the visible and near-infrared ranges as a non-invasive method of discrimination between different red organic pigments in cultural heritage objects. Based on reconstructions of paints used in the period extending from the fourteenth to the sixteenth century, prepared with as far as possible historical accuracy, the analyses by means of visible/near-infrared reflectance hyperspectral imaging were carried out with the objective of understanding the most significant differences between these vegetal- and animal-based red lake pigments. The paper discusses the results that were obtained on four original Italian and North European paintings and compared with those from the paint reconstructions, in order to demonstrate how the hyperspectral imaging technique can be usefully and effectively applied to the identification and mapping of red lake pigments in painted surfaces of interest in the conservation field.

  18. 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.

  19. Retooling Laser Speckle Contrast Analysis Algorithm to Enhance Non-Invasive High Resolution Laser Speckle Functional Imaging of Cutaneous Microcirculation

    PubMed Central

    Gnyawali, Surya C.; Blum, Kevin; Pal, Durba; Ghatak, Subhadip; Khanna, Savita; Roy, Sashwati; Sen, Chandan K.

    2017-01-01

    Cutaneous microvasculopathy complicates wound healing. Functional assessment of gated individual dermal microvessels is therefore of outstanding interest. Functional performance of laser speckle contrast imaging (LSCI) systems is compromised by motion artefacts. To address such weakness, post-processing of stacked images is reported. We report the first post-processing of binary raw data from a high-resolution LSCI camera. Sharp images of low-flowing microvessels were enabled by introducing inverse variance in conjunction with speckle contrast in Matlab-based program code. Extended moving window averaging enhanced signal-to-noise ratio. Functional quantitative study of blood flow kinetics was performed on single gated microvessels using a free hand tool. Based on detection of flow in low-flow microvessels, a new sharp contrast image was derived. Thus, this work presents the first distinct image with quantitative microperfusion data from gated human foot microvasculature. This versatile platform is applicable to study a wide range of tissue systems including fine vascular network in murine brain without craniotomy as well as that in the murine dorsal skin. Importantly, the algorithm reported herein is hardware agnostic and is capable of post-processing binary raw data from any camera source to improve the sensitivity of functional flow data above and beyond standard limits of the optical system. PMID:28106129

  20. Non-invasive imaging in coronary artery disease including anatomical and functional evaluation of ischaemia and viability assessment

    PubMed Central

    Pakkal, M; Raj, V; Mccann, G P

    2011-01-01

    Coronary artery disease has an important impact on the morbidity and mortality statistics and health economics worldwide. Diagnosis of coronary artery disease is important in risk stratification and guides further management. Invasive coronary angiography is the traditional method of imaging the coronary arteries and remains the gold standard. It detects luminal stenosis but provides little information about the vessel wall or plaques. Besides, not all anatomical lesions are functionally significant. This has lent itself to a wide variety of imaging techniques to identify and assess a flow-limiting stenosis. The approach to diagnosis of coronary artery disease is broadly based on anatomical and functional imaging. Coronary CT and MRI of coronary arteries provide an anatomical assessment of coronary stenosis. Coronary calcium score and coronary CT assess subclinical atherosclerosis by assessing the atherosclerotic plaque burden. The haemodynamic significance of a coronary artery stenosis can be assessed by stress radioisotope studies, stress echocardiography and stress MRI. The more recent literature also focuses on plaque assessment and identification of plaques that are likely to give rise to an acute coronary syndrome. There is an explosion of literature on the merits and limitations of the different imaging modalities. This review article will provide an overview of all the imaging modalities in the diagnosis of coronary artery disease. PMID:22723535

  1. Retooling Laser Speckle Contrast Analysis Algorithm to Enhance Non-Invasive High Resolution Laser Speckle Functional Imaging of Cutaneous Microcirculation

    NASA Astrophysics Data System (ADS)

    Gnyawali, Surya C.; Blum, Kevin; Pal, Durba; Ghatak, Subhadip; Khanna, Savita; Roy, Sashwati; Sen, Chandan K.

    2017-01-01

    Cutaneous microvasculopathy complicates wound healing. Functional assessment of gated individual dermal microvessels is therefore of outstanding interest. Functional performance of laser speckle contrast imaging (LSCI) systems is compromised by motion artefacts. To address such weakness, post-processing of stacked images is reported. We report the first post-processing of binary raw data from a high-resolution LSCI camera. Sharp images of low-flowing microvessels were enabled by introducing inverse variance in conjunction with speckle contrast in Matlab-based program code. Extended moving window averaging enhanced signal-to-noise ratio. Functional quantitative study of blood flow kinetics was performed on single gated microvessels using a free hand tool. Based on detection of flow in low-flow microvessels, a new sharp contrast image was derived. Thus, this work presents the first distinct image with quantitative microperfusion data from gated human foot microvasculature. This versatile platform is applicable to study a wide range of tissue systems including fine vascular network in murine brain without craniotomy as well as that in the murine dorsal skin. Importantly, the algorithm reported herein is hardware agnostic and is capable of post-processing binary raw data from any camera source to improve the sensitivity of functional flow data above and beyond standard limits of the optical system.

  2. Non-invasive magnetic resonance imaging diagnosis of presumed intermedioradial carpal bone avascular necrosis in the dog

    PubMed Central

    Pownder, Sarah L.; Cooley, Stacy; Hayashi, Kei; Bezuidenhout, Abraham; Koff, Matthew F.; Potter, Hollis G.

    2016-01-01

    A 5-year-old, spayed female Weimaraner dog was evaluated for progressive left forelimb lameness localized to the carpus. Magnetic resonance imaging (MRI) was used to arrive at a presumptive diagnosis of intermedioradial carpal (IRC) bone fracture with avascular necrosis (AVN). To the authors’ knowledge, this is the first report of naturally occurring AVN of the canine IRC diagnosed using MRI. PMID:27493290

  3. History of Mexican Easel Paintings from an Altarpiece Revealed by Non-invasive Terahertz Time-Domain Imaging

    NASA Astrophysics Data System (ADS)

    Gomez-Sepulveda, A. M.; Hernandez-Serrano, A. I.; Radpour, R.; Koch-Dandolo, C. L.; Rojas-Landeros, S. C.; Ascencio-Rojas, L. F.; Zarate, Alvaro; Hernandez, Gerardo; Gonzalez-Tirado, R. C.; Insaurralde-Caballero, M.; Castro-Camus, E.

    2016-12-01

    Four easel paintings attributed to Hermenegildo Bustos (Purísima del Rincón, Guanajuato, Mexico), one of the most renowned painters of the late nineteenth and early twentieth century Mexican art, have been investigated by means of terahertz time-domain imaging (THz-TDI) and standard imaging techniques, such as near-IR reflectography and X-ray radiography. The archival sources and the recent studies on the paintings suggest that the artworks were created in the eighteenth century and underwent several modifications since then until the intervention of Bustos who authored the currently visible depictions. By combining the records of the paintings obtained by imaging with the different methodologies, aspects of the previous depictions and further details on the paintings' history have been revealed, with THz-TDI playing a key role in attributing a chronological evolution of the images. The paintings of Purísima are the first THz-TDI-scanned paintings belonging to the Mexican cultural heritage.

  4. History of Mexican Easel Paintings from an Altarpiece Revealed by Non-invasive Terahertz Time-Domain Imaging

    NASA Astrophysics Data System (ADS)

    Gomez-Sepulveda, A. M.; Hernandez-Serrano, A. I.; Radpour, R.; Koch-Dandolo, C. L.; Rojas-Landeros, S. C.; Ascencio-Rojas, L. F.; Zarate, Alvaro; Hernandez, Gerardo; Gonzalez-Tirado, R. C.; Insaurralde-Caballero, M.; Castro-Camus, E.

    2017-04-01

    Four easel paintings attributed to Hermenegildo Bustos ( Purísima del Rincón, Guanajuato, Mexico), one of the most renowned painters of the late nineteenth and early twentieth century Mexican art, have been investigated by means of terahertz time-domain imaging (THz-TDI) and standard imaging techniques, such as near-IR reflectography and X-ray radiography. The archival sources and the recent studies on the paintings suggest that the artworks were created in the eighteenth century and underwent several modifications since then until the intervention of Bustos who authored the currently visible depictions. By combining the records of the paintings obtained by imaging with the different methodologies, aspects of the previous depictions and further details on the paintings' history have been revealed, with THz-TDI playing a key role in attributing a chronological evolution of the images. The paintings of Purísima are the first THz-TDI-scanned paintings belonging to the Mexican cultural heritage.

  5. Nonlinear spectroscopy in the near-field: time resolved spectroscopy and subwavelength resolution non-invasive imaging

    NASA Astrophysics Data System (ADS)

    Namboodiri, Mahesh; Khan, Tahirzeb; Karki, Khadga; Kazemi, Mehdi Mohammad; Bom, Sidhant; Flachenecker, Günter; Namboodiri, Vinu; Materny, Arnulf

    2014-04-01

    The combination of near-field microscopy along with nonlinear optical spectroscopic techniques is presented here. The scanning near-field imaging technique can be integrated with nonlinear spectroscopic techniques to improve spatial and axial resolution of the images. Additionally, ultrafast dynamics can be probed down to nano-scale dimension. The review shows some examples for this combination, which resulted in an exciton map and vibrational contrast images with sub-wavelength resolution. Results of two-color femtosecond time-resolved pump-probe experiments using scanning near-field optical microscopy (SNOM) on thin films of the organic semiconductor 3,4,9,10 Perylenetetracarboxylic dianhydride (PTCDA) are presented. While nonlinear Raman techniques have been used to obtain highly resolved images in combination with near-field microscopy, the use of femtosecond laser pulses in electronic resonance still constitutes a big challenge. Here, we present our first results on coherent anti-Stokes Raman scattering (fs-CARS) with femtosecond laser pulses detected in the near-field using SNOM. We demonstrate that highly spatially resolved images can be obtained from poly(3-hexylthiophene) (P3HT) nano-structures where the fs-CARS process was in resonance with the P3HT absorption and with characteristic P3HT vibrational modes without destruction of the samples. Sub-diffraction limited lateral resolution is achieved. Especially the height resolution clearly surpasses that obtained with standard microCARS. These results will be the basis for future investigations of mode-selective dynamics in the near-field.

  6. Combination of optoacoustics and ultrasound imaging for non-invasive, rapid assessment, and management of circulatory shock

    NASA Astrophysics Data System (ADS)

    Petrov, Yuriy; Petrov, Irene Y.; Esenaliev, Rinat O.; Kinsky, Michael; Prough, Donald S.

    2011-03-01

    We developed a noninvasive, optoacoustic diagnostic platform for monitoring of multiple physiologic variables in inpatients and outpatients. One of the most important applications of this platform is noninvasive, rapid assessment and management of circulatory shock, a common condition in critically ill patients. At present, monitoring of circulatory shock requires measurement of central venous blood oxygenation using invasive procedures such as insertion of catheters in central veins. Hemoglobin saturation below 70% in central veins indicates circulatory shock that requires immediate treatment. We built a portable optoacoustic system for noninvasive measurement of central venous oxygenation. In this study we used the optoacoustic system and clinical ultrasound imaging systems for rapid optoacoustic probing of these veins. The optoacoustic system utilizes a custom-made, sensitive optoacoustic probe that was developed in our laboratory for monitoring of blood oxygenation in deep blood vessels. The studies were performed in human subjects with different geometry (depth, size) of the veins. The ultrasound imaging systems permitted rapid identification of specific blood vessels for optoacoustic probing. We developed a novel algorithm for continuous, realtime, and precise measurement of blood oxygenation in blood vessels. Precision of central venous oxygenation measurement obtained in the study was very high: 1%. Our results indicate that the combination of optoacoustics and ultrasound imaging systems can provide more rapid and accurate assessment and management of the circulatory shock.

  7. Melanomas non-invasive diagnosis application based on the ABCD rule and pattern recognition image processing algorithms.

    PubMed

    Isasi, A Gola; Zapirain, B García; Zorrilla, A Méndez

    2011-09-01

    In this paper an automated dermatological tool for the parameterization of melanomas is presented. The system is based on the standard ABCD Rule and dermatological Pattern Recognition protocols. On the one hand, a complete stack of algorithms for the asymmetry, border, color, and diameter parameterization were developed. On the other hand, three automatic algorithms for digital image processing have been developed in order to detect the appropriate patterns. These allow one to calculate certain quantitative features based on the aspect and inner patterns of the melanoma using simple-operation algorithms, in order to minimize response time. The database used consists of 160 500 x 500-pixel RGB images (20 images per pattern) cataloged by dermatologists, and the results have turned out to be successful according to assessment by medical experts. While the ABCD algorithms are mathematically reliable, the proposed algorithms for pattern recognition produced a remarkable rate of globular, reticular, and blue veil Pattern recognition, with an average above 85% of accuracy. It thus proves to be a reliable system when performing a diagnosis.

  8. Quantitative phase imaging of cellular and subcellular structures for non-invasive screening diagnostics of socially significant diseases

    NASA Astrophysics Data System (ADS)

    Vasilenko, Irina; Metelin, Vladislav; Nasyrov, Marat; Belyakov, Vladimir; Kuznetsov, Alexander; Sukhenko, Evgeniy

    2015-03-01

    The objective of the present study is to increase the quality of the early diagnosis using cytological differential-diagnostic criteria for reactive changes in the nuclear structures of the immunocompetent cells. The morphofunctional status of living cells were estimated in the real time using new technologic platform of the hardware-software complex for phase cell imaging. The level of functional activity for lymphocyte subpopulations was determined on the base of modification of nuclear structures and decreasing of nuclear phase thickness. The dynamics of nuclear parameters was used as the quantitative measuring for cell activating level and increasing of proliferative potential.

  9. Non-invasive neurochemical analysis of focal excitotoxic lesions in models of neurodegenerative illness using spectroscopic imaging.

    PubMed

    Jenkins, B G; Brouillet, E; Chen, Y C; Storey, E; Schulz, J B; Kirschner, P; Beal, M F; Rosen, B R

    1996-05-01

    Water-suppressed chemical shift magnetic resonance imaging was used to detect neurochemical alterations in vivo in neurotoxin-induced rat models of Huntington's and Parkinson's disease. The toxins were: N-methyl-4-phenylpyridinium (MPP+), aminooxyacetic acid (AOAA), 3-nitropropionic acid (3-NP), malonate, and azide. Local or systemic injection of these compounds caused secondary excitotoxic lesions by selective inhibition of mitochondrial respiration that gave rise to elevated lactate concentrations in the striatum. In addition, decreased N-acetylaspartate (NAA) concentrations were noted at the lesion site over time. Measurements of lactate washout kinetics demonstrated that t1/2 followed the order: 3-NP approximately MPP+ > AOAA approximately malonate, which parallels the expected lifetimes of the neurotoxins based on their mechanisms of action. Further increases in lactate were also caused by intravenous infusion of glucose. At least part of the excitotoxicity is mediated through indirect glutamate pathways because lactate production and lesion size were diminished using unilateral decortectomies (blockade of glutamatergic input) or glutamate antagonists (MK-801). Lesion size and lactate were also diminished by energy repletion with ubiquinone and nicotinamide. Lactate measurements determined by magnetic resonance agreed with biochemical measurements made using freeze clamp techniques. Lesion size as measured with MR, although larger by 30%, agreed well with lesion size determined histologically. These experiments provide evidence for impairment of intracellular energy metabolism leading to indirect excitotoxicity for all the compounds mentioned before and demonstrate the feasibility of small-volume metabolite imaging for in vivo neurochemical analysis.

  10. A Biocompatible In Vivo Ligation Reaction and its Application for Non-Invasive Bioluminescent Imaging of Protease Activity in Living Mice

    PubMed Central

    Godinat, Aurélien; Park, Hyo Min; Miller, Stephen C.; Cheng, Ke; Hanahan, Douglas; Sanman, Laura E.; Bogyo, Matthew; Yu, Allen; Nikitin, Gennady F.; Stahl, Andreas; Dubikovskaya, Elena A.

    2013-01-01

    The discovery of biocompatible reactions has had a tremendous impact on chemical biology, allowing the study of numerous biological processes directly in complex systems. However, despite the fact that multiple biocompatible reactions have been developed in the past decade, very few work well in living mice. Here we report that D-cysteine and 2-cyanobenzothiazoles can selectively react with each other in vivo to generate a luciferin substrate for firefly luciferase. The success of this “split luciferin” ligation reaction has important implications for both in vivo imaging and biocompatible labeling strategies. First, the production of a luciferin substrate can be visualized in a live mouse by bioluminescence imaging (BLI), and furthermore allows interrogation of targeted tissues using a “caged” luciferin approach. We therefore applied this reaction to the real-time non-invasive imaging of apoptosis associated with caspase 3/7. Caspase-dependent release of free D-cysteine from the caspase 3/7 peptide substrate Asp-Glu-Val-Asp-D-Cys (DEVD-(D-Cys)) allowed selective reaction with 6-amino-2-cyanobenzothiazole (NH2-CBT) in vivo to form 6-amino-D-luciferin with subsequent light emission from luciferase. Importantly, this strategy was found to be superior to the commercially-available DEVD-aminoluciferin substrate for imaging of caspase 3/7 activity. Moreover, the split luciferin approach enables the modular construction of bioluminogenic sensors, where either or both reaction partners could be caged to report on multiple biological events. Lastly, the luciferin ligation reaction is three orders of magnitude faster than Staudinger ligation suggesting further applications for both bioluminescence and specific molecular targeting in vivo. PMID:23463944

  11. Non-invasive, whole-plant imaging of chloroplast movement and chlorophyll fluorescence reveals photosynthetic phenotypes independent of chloroplast photorelocation defects in chloroplast division mutants.

    PubMed

    Dutta, Siddhartha; Cruz, Jeffrey A; Jiao, Yuhua; Chen, Jin; Kramer, David M; Osteryoung, Katherine W

    2015-10-01

    Leaf chloroplast movement is thought to optimize light capture and to minimize photodamage. To better understand the impact of chloroplast movement on photosynthesis, we developed a technique based on the imaging of reflectance from leaf surfaces that enables continuous, high-sensitivity, non-invasive measurements of chloroplast movement in multiple intact plants under white actinic light. We validated the method by measuring photorelocation responses in Arabidopsis chloroplast division mutants with drastically enlarged chloroplasts, and in phototropin mutants with impaired photorelocation but normal chloroplast morphology, under different light regimes. Additionally, we expanded our platform to permit simultaneous image-based measurements of chlorophyll fluorescence and chloroplast movement. We show that chloroplast division mutants with enlarged, less-mobile chloroplasts exhibit greater photosystem II photodamage than is observed in the wild type, particularly under fluctuating high levels of light. Comparison between division mutants and the severe photorelocation mutant phot1-5 phot2-1 showed that these effects are not entirely attributable to diminished photorelocation responses, as previously hypothesized, implying that altered chloroplast morphology affects other photosynthetic processes. Our dual-imaging platform also allowed us to develop a straightforward approach to correct non-photochemical quenching (NPQ) calculations for interference from chloroplast movement. This correction method should be generally useful when fluorescence and reflectance are measured in the same experiments. The corrected data indicate that the energy-dependent (qE) and photoinhibitory (qI) components of NPQ contribute differentially to the NPQ phenotypes of the chloroplast division and photorelocation mutants. This imaging technology thus provides a platform for analyzing the contributions of chloroplast movement, chloroplast morphology and other phenotypic attributes to the

  12. Non-invasive Imaging and Tracking of Engineered Human Muscle Precursor Cells for Skeletal Muscle Tissue Engineering Using Positron Emission Tomography

    PubMed Central

    Haralampieva, Deana; Betzel, Thomas; Dinulovic, Ivana; Salemi, Souzan; Stoelting, Meline; Kraemer, Stefanie; Schibli, Roger; Sulser, Tullio; Handschin, Christoph; Eberli, Daniel; Ametamey, Simon M.

    2016-01-01

    Transplantation of human muscle precursor cells (hMPCs) is envisioned for the treatment of various muscle diseases. However, a feasible non-invasive tool to monitor cell survival, migration and integration into the host tissue is still missing. Methods In this study, we designed an adenoviral delivery system to genetically modify hMPCs to express a signaling-deficient form of a human dopamine D2 receptor (hD2R). The gene expression levels of the receptor were evaluated by Reverse Transcriptase Polymerase Chain Reaction (RTPCR) and infection efficiency was visualized by fluorescent microscopy. Viability, proliferation and differentiation capacity of the transduced cells were confirmed and their sustained myogenic phenotype was shown by flow cytometry analysis and fluorescent microscopy. 18F-Fallypride and 18F-FMISO, two well-established PET radioligands, were successfully synthesized and evaluated for their potential to image engineered hMPCs in a mouse model. Furthermore, biodistribution studies and autoradiography were also performed to determine the extent of signal specificity. Results To address the feasibility of the presented approach for tracking of hMPCs in an in vivo model, we first evaluated the safety of the adenoviral gene-delivery, which showed no detrimental effects on the primary human cells. Specific binding of 18F-Fallypride to hD2R_hMPCs was demonstrated in vitro, as well as in vivo, by performing autoradiography, biodistribution and PET experiments, respectively. Furthermore, 18F-FMISO uptake was evaluated at different time-points after cell inoculation in vivo, showing high signal only at the early stages. Finally, histological assessment of the harvested tissues confirmed the sustained survival of the transplanted cells at different time-points with formation of muscle tissue at the site of injection. Conclusion We here propose a signaling-deficient human D2R as a potent reporter for in vivo hMPCs PET tracking by 18F-Fallypride. This approach

  13. Non-invasive skin oxygenation imaging using a multi-spectral camera system: effectiveness of various concentration algorithms applied on human skin

    NASA Astrophysics Data System (ADS)

    Klaessens, John H. G. M.; Noordmans, Herke Jan; de Roode, Rowland; Verdaasdonk, Rudolf M.

    2009-02-01

    This study describes noninvasive noncontact methods to acquire and analyze functional information from the skin. Multispectral images at several selected wavelengths in the visible and near infrared region are collected and used in mathematical methods to calculate concentrations of different chromophores in the epidermis and dermis of the skin. This is based on the continuous wave Near Infrared Spectroscopy method, which is a well known non-invasive technique for measuring oxygenation changes in the brain and in muscle tissue. Concentration changes of hemoglobin (dO2Hb, dHHb and dtHb) can be calculated from light attenuations using the modified Lambert Beer equation. We applied this technique on multi-spectral images taken from the skin surface using different algorithms for calculating changes in O2Hb, HHb and tHb. In clinical settings, the imaging of local oxygenation variations and/or blood perfusion in the skin can be useful for e.g. detection of skin cancer, detection of early inflammation, checking the level of peripheral nerve block anesthesia, study of wound healing and tissue viability by skin flap transplantations. Images from the skin are obtained with a multi-spectral imaging system consisting of a 12-bit CCD camera in combination with a Liquid Crystal Tunable Filter. The skin is illuminated with either a broad band light source or a tunable multi wavelength LED light source. A polarization filter is used to block the direct reflected light. The collected multi-spectral imaging data are images of the skin surface radiance; each pixel contains either the full spectrum (420 - 730 nm) or a set of selected wavelengths. These images were converted to reflectance spectra. The algorithms were validated during skin oxygen saturation changes induced by temporary arm clamping and applied to some clinical examples. The initial results with the multi-spectral skin imaging system show good results for detecting dynamic changes in oxygen concentration. However, the

  14. Non Invasive High Resolution In Vivo Imaging of α-napthylisothiocyanate (ANIT) Induced Hepatobiliary Toxicity in STII Medaka

    PubMed Central

    Hardman, Ron; Kullman, Seth; Yuen, Bonny; Hinton, David E.

    2009-01-01

    A novel transparent stock of medaka (Oryzias latipes; STII), homozygous recessive for all four pigments (iridophores, xanthophores, leucophores, melanophores), permits transcutaneous, high resolution ( < 1μm) imaging of internal organs and tissues in living individuals. We applied this model to in vivo investigation of α-napthylisothiocyanate (ANIT) induced hepatobiliary toxicity. Distinct phenotypic responses to ANIT involving all aspects of intrahepatic biliary passageways (IHBPs), particularly bile preductular epithelial cells (BPDECs), associated with transitional passageways between canaliculi and bile ductules, were observed. Alterations included: attenuation/dilation of bile canaliculi, bile preductular lesions, hydropic vacuolation of hepatocytes and BPDECs, mild BPDEC hypertrophy, and biliary epithelial cell (BEC) hyperplasia. Ex vivo histological, immunohistochemical, and ultrastructural studies were employed to aid in interpretation of, and verify, in vivo findings. 3D reconstructions from in vivo investigations provided quantitative morphometric and volumetric evaluation of ANIT exposed and untreated livers. The findings presented show for the first time in vivo evaluation of toxicity in the STII medaka hepatobiliary system, and, in conjunction with prior in vivo work characterizing normalcy, advance our comparative understanding of this lower vertebrate hepatobiliary system and its response to toxic insult. PMID:18022256

  15. Identifying Model Inaccuracies and Solution Uncertainties in Non-Invasive Activation-Based Imaging of Cardiac Excitation using Convex Relaxation

    PubMed Central

    Erem, Burak; van Dam, Peter M.; Brooks, Dana H.

    2014-01-01

    Noninvasive imaging of cardiac electrical function has begun to move towards clinical adoption. Here we consider one common formulation of the problem, in which the goal is to estimate the spatial distribution of electrical activation times during a cardiac cycle. We address the challenge of understanding the robustness and uncertainty of solutions to this formulation. This formulation poses a non-convex, non-linear least squares optimization problem. We show that it can be relaxed to be convex, at the cost of some degree of physiological realism of the solution set, and that this relaxation can be used as a framework to study model inaccuracy and solution uncertainty. We present two examples, one using data from a healthy human subject and the other synthesized with the ECGSIM software package. In the first case, we consider uncertainty in the initial guess and regularization parameter. In the second case, we mimic the presence of an ischemic zone in the heart in a way which violates a model assumption. We show that the convex relaxation allows understanding of spatial distribution of parameter sensitivity in the first case, and identification of model violation in the second. PMID:24710159

  16. A pH-activatable nanoparticle with signal-amplification capabilities for non-invasive imaging of tumour malignancy

    NASA Astrophysics Data System (ADS)

    Mi, Peng; Kokuryo, Daisuke; Cabral, Horacio; Wu, Hailiang; Terada, Yasuko; Saga, Tsuneo; Aoki, Ichio; Nishiyama, Nobuhiro; Kataoka, Kazunori

    2016-08-01

    Engineered nanoparticles that respond to pathophysiological parameters, such as pH or redox potential, have been developed as contrast agents for the magnetic resonance imaging (MRI) of tumours. However, beyond anatomic assessment, contrast agents that can sense these pathological parameters and rapidly amplify their magnetic resonance signals are desirable because they could potentially be used to monitor the biological processes of tumours and improve cancer diagnosis. Here, we report an MRI contrast agent that rapidly amplifies magnetic resonance signals in response to pH. We confined Mn2+ within pH-sensitive calcium phosphate (CaP) nanoparticles comprising a poly(ethylene glycol) shell. At a low pH, such as in solid tumours, the CaP disintegrates and releases Mn2+ ions. Binding to proteins increases the relaxivity of Mn2+ and enhances the contrast. We show that these nanoparticles could rapidly and selectively brighten solid tumours, identify hypoxic regions within the tumour mass and detect invisible millimetre-sized metastatic tumours in the liver.

  17. Non-invasive evaluation of neuroprotective drug candidates for cerebral infarction by PET imaging of mitochondrial complex-I activity

    PubMed Central

    Fukuta, Tatsuya; Asai, Tomohiro; Ishii, Takayuki; Koide, Hiroyuki; Kiyokawa, Chiaki; Hashimoto, Masahiro; Kikuchi, Takashi; Shimizu, Kosuke; Harada, Norihiro; Tsukada, Hideo; Oku, Naoto

    2016-01-01

    The development of a diagnostic technology that can accurately determine the pathological progression of ischemic stroke and evaluate the therapeutic effects of cerebroprotective agents has been desired. We previously developed a novel PET probe, 2-tert-butyl-4-chloro-5-{6-[2-(2-18F-fluoroethoxy)-ethoxy]-pyridin-3-ylmethoxy}-2H-pyridazin-3-one ([18F]BCPP-EF) for detecting activity of mitochondrial complex I (MC-I). This probe was shown to visualize neuronal damage in the living brain of rodent and primate models of neurodegenerative diseases. In the present study, [18F]BCPP-EF was applied to evaluate the therapeutic effects of a neuroprotectant, liposomal FK506 (FK506-liposomes), on cerebral ischemia/reperfusion (I/R) injury in transient middle cerebral artery occlusion rats. The PET imaging using [18F]BCPP-EF showed a prominent reduction in the MC-I activity in the ischemic brain hemisphere. Treatment with FK506-liposomes remarkably increased the uptake of [18F]BCPP-EF in the ischemic side corresponding to the improvement of blood flow disorders and motor function deficits throughout the 7 days after I/R. Additionally, the PET scan could diagnose the extent of the brain damage accurately and showed the neuroprotective effect of FK506-liposomes at Day 7, at which 2, 3, 5-triphenyltetrazolium chloride staining couldn’t visualize them. Our study demonstrated that the PET technology using [18F]BCPP-EF has a potent capacity to evaluate the therapeutic effect of drug candidates in living brain. PMID:27440054

  18. Non-invasive assessment of liver fibrosis in a rat model: shear wave elasticity imaging versus real-time elastography.

    PubMed

    Lin, Sen-Hao; Ding, Hong; Mao, Feng; Xue, Li-Yun; Lv, Wei-Wei; Zhu, Hong-Guang; Huang, Bei-Jian; Wang, Wen-Ping

    2013-07-01

    The purpose of this study was to investigate the diagnostic value of shear wave elasticity imaging (SWEI) and real-time elastography (RTE) in liver fibrosis induced by dimethylnitrosamine (DMN) and to compare the accuracy of these methods. Seventy male Wistar rats given a single intra-peritoneal injection of DMN and 10 control rats given a saline injection underwent SWEI and RTE to determine their shear wave velocity (V(s)) and liver fibrosis (LF) index, respectively. Correlations between V(s) or the LF index and histologic stage of liver fibrosis (S0-S4) were analyzed, and the diagnostic values of the techniques were assessed using a receiver operating characteristic curve. A positive correlation was found between V(s) and stage of liver fibrosis (r = 0.947, p < 0.001) and between LF index and stage (S) of liver fibrosis (r = 0.662, p < 0.001). For Vs, the areas under the receiver operating characteristic curve for the diagnosis of fibrosis, S ≥ S1, S ≥ S2, S ≥ S3 and S = S4, were 0.983, 0.995, 0.999 and 0.964, respectively; for the LF index, the values were 0.871, 0.887, 0.761 and 0.839, respectively (all p < 0.001). Vs and the LF index values in rats with severe inflammatory activity were significantly higher than those in controls (p < 0.001). In conclusion, positive correlations exist between V(s) or the LF index and the severity of liver fibrosis in rats. Vs is more accurate than the LF index in predicting liver fibrosis in rats. However, severe inflammatory activity may reduce the accuracy of both techniques.

  19. Non-invasive evaluation of neuroprotective drug candidates for cerebral infarction by PET imaging of mitochondrial complex-I activity

    NASA Astrophysics Data System (ADS)

    Fukuta, Tatsuya; Asai, Tomohiro; Ishii, Takayuki; Koide, Hiroyuki; Kiyokawa, Chiaki; Hashimoto, Masahiro; Kikuchi, Takashi; Shimizu, Kosuke; Harada, Norihiro; Tsukada, Hideo; Oku, Naoto

    2016-07-01

    The development of a diagnostic technology that can accurately determine the pathological progression of ischemic stroke and evaluate the therapeutic effects of cerebroprotective agents has been desired. We previously developed a novel PET probe, 2-tert-butyl-4-chloro-5-{6-[2-(2-18F-fluoroethoxy)-ethoxy]-pyridin-3-ylmethoxy}-2H-pyridazin-3-one ([18F]BCPP-EF) for detecting activity of mitochondrial complex I (MC-I). This probe was shown to visualize neuronal damage in the living brain of rodent and primate models of neurodegenerative diseases. In the present study, [18F]BCPP-EF was applied to evaluate the therapeutic effects of a neuroprotectant, liposomal FK506 (FK506-liposomes), on cerebral ischemia/reperfusion (I/R) injury in transient middle cerebral artery occlusion rats. The PET imaging using [18F]BCPP-EF showed a prominent reduction in the MC-I activity in the ischemic brain hemisphere. Treatment with FK506-liposomes remarkably increased the uptake of [18F]BCPP-EF in the ischemic side corresponding to the improvement of blood flow disorders and motor function deficits throughout the 7 days after I/R. Additionally, the PET scan could diagnose the extent of the brain damage accurately and showed the neuroprotective effect of FK506-liposomes at Day 7, at which 2, 3, 5-triphenyltetrazolium chloride staining couldn’t visualize them. Our study demonstrated that the PET technology using [18F]BCPP-EF has a potent capacity to evaluate the therapeutic effect of drug candidates in living brain.

  20. The Assessment of Inter-Hemispheric Imbalance using Imaging and Non-Invasive Brain Stimulation in Patients with Chronic Stroke

    PubMed Central

    Cunningham, David A.; Machado, Andre; Janini, Daniel; Varnerin, Nicole; Bonnett, Corin; Yue, Guang; Jones, Stephen; Lowe, Mark; Beall, Erik; Sakaie, Ken; Plow, Ela B.

    2014-01-01

    OBJECTIVE To determine how inter-hemispheric balance in stroke, measured using transcranial magnetic stimulation (TMS), relates to balance defined using neuroimaging (functional magnetic resonance (fMRI) and diffusion tensor imaging (DTI)), and how these metrics of balance are associated with clinical measures of upper limb function and disability. DESIGN Cross-Sectional SETTING Clinical Research Laboratory PARTICIPANTS Ten chronic stroke patients (63±9 years) in a population based sample with unilateral upper-limb paresis. INTERVENTION Not applicable MAIN OUTCOME MEASURES Inter-hemispheric balance was measured with TMS, fMRI and DTI. TMS defined inter-hemispheric differences in recruitment of corticospinal output, the size of the corticomotor output maps and the degree of mutual transcallosal inhibition they exerted upon one another. fMRI studied whether cortical activation during the movement of the paretic hand was lateralized to the ipsilesional or to the contralesional primary motor (M1), premotor (PMC) and supplementary motor cortices (SMA). DTI was used to define inter-hemispheric differences in the integrity of the corticospinal tracts projecting from M1. Clinical outcomes tested function (upper-extremity Fugl-Meyer (UEFM) and the perceived disability in the use of the paretic hand [Motor Activity Log (MAL)]. RESULTS Inter-hemispheric balance assessed with TMS relates differently to fMRI and DTI. Patients with high fMRI lateralization to the ipsilesional hemisphere possessed stronger ipsilesional corticomotor output maps [M1 (r=.831, p=.006), PMC (r=.797, p=.01)], and better balance of mutual transcallosal inhibition (r=.810, p=.015). Conversely, we have found that patients with less integrity of the corticospinal tracts in the ipsilesional hemisphere show greater corticospinal output of homologous tracts in the contralesional hemisphere (r=.850, p=.004). However, neither an imbalance in their integrity nor an imbalance of their output relates to

  1. 3D magnetic resonance imaging as a non-invasive tool for investigating water-filled karst formations

    NASA Astrophysics Data System (ADS)

    Legchenko, A.; Ezersky, M.; Boucher, M.; Chevalier, A.; Vouillamoz, J.-M.

    2012-04-01

    Magnetic Resonance Sounding (MRS) is a geophysical technique developed for groundwater exploration. MRS can be used for reliable identification of karst aquifers because of the relaxation time of the magnetic resonance signal (T1) is longer for bulk water in karst caverns and channels (about 2 s) than for water in porous rock (few tens of ms). MRS is sensitive primary to groundwater volume but electrically conductive layers modify electromagnetic fields in the subsurface and thus may have an effect on MRS performance. Generally, the study of a karst requires a 3D field set-up and we developed a measuring procedure and interpretation software that makes it possible to image heterogeneous water-bearing geological formations down to about 80 m (3D-SNMR method). Numerical modeling results show that limited resolution of the method allows only identification of large karst formations. For example detectable karst should be larger than a few hundred cubic meters when karst is located close to the surface and a few thousand cubic meters when it is located at 60 m. Time Domain Electromagnetic method (TDEM) is known as an efficient tool for investigating electrical conductivity of rocks. TDEM results allow more accurate computing of the EM field in the subsurface and thus contribute for improving accuracy of MRS results. TDEM and 3D-SNMR methods were applied jointly in the Dead Sea coast of Israel (Nahal Hever South). The subsurface in this area is heterogeneous and composed of intercalated sand and clay layers over a salt rock, which is partly karstified. Groundwater is very saline, with a chloride concentration of 100-225 g/l thus rendering the resistivity of geological formations less than 1 ohm-m. We have shown numerically that under Dead Sea coast conditions, 3D-SNMR is able to detect and to locate the target within an error of a few tens of meters. In the investigated area (500×500 m2) our results reveal a very heterogeneous shallow aquifer that could be divided into

  2. Feasibility of non-invasive temperature estimation by the assessment of the average gray-level content of B-mode images.

    PubMed

    Teixeira, C A; Alvarenga, A V; Cortela, G; von Krüger, M A; Pereira, W C A

    2014-08-01

    This paper assesses the potential of the average gray-level (AVGL) from ultrasonographic (B-mode) images to estimate temperature changes in time and space in a non-invasive way. Experiments were conducted involving a homogeneous bovine muscle sample, and temperature variations were induced by an automatic temperature regulated water bath, and by therapeutic ultrasound. B-mode images and temperatures were recorded simultaneously. After data collection, regions of interest (ROIs) were defined, and the average gray-level variation computed. For the selected ROIs, the AVGL-Temperature relation were determined and studied. Based on uniformly distributed image partitions, two-dimensional temperature maps were developed for homogeneous regions. The color-coded temperature estimates were first obtained from an AVGL-Temperature relation extracted from a specific partition (where temperature was independently measured by a thermocouple), and then extended to the other partitions. This procedure aimed to analyze the AVGL sensitivity to changes not only in time but also in space. Linear and quadratic relations were obtained depending on the heating modality. We found that the AVGL-Temperature relation is reproducible over successive heating and cooling cycles. One important result was that the AVGL-Temperature relations extracted from one region might be used to estimate temperature in other regions (errors inferior to 0.5 °C) when therapeutic ultrasound was applied as a heating source. Based on this result, two-dimensional temperature maps were developed when the samples were heated in the water bath and also by therapeutic ultrasound. The maps were obtained based on a linear relation for the water bath heating, and based on a quadratic model for the therapeutic ultrasound heating. The maps for the water bath experiment reproduce an acceptable heating/cooling pattern, and for the therapeutic ultrasound heating experiment, the maps seem to reproduce temperature profiles

  3. A non-invasive in vivo imaging system to study dissemination of bioluminescent Yersinia pestis CO92 in a mouse model of pneumonic plague

    PubMed Central

    Sha, Jian; Rosenzweig, Jason A.; Kirtley, Michelle L.; van Lier, Christina J.; Fitts, Eric C.; Kozlova, Elena V.; Erova, Tatiana E.; Tiner, Bethany L.; Chopra, Ashok K.

    2012-01-01

    The gold standard in microbiology for monitoring bacterial dissemination in infected animals has always been viable plate counts. This method, despite being quantitative, requires sacrificing the infected animals. Recently, however, an alternative method of in vivo imaging of bioluminescent bacteria (IVIBB) for monitoring microbial dissemination within the host has been employed. Yersina pestis is a Gram-negative bacterium capable of causing bubonic, septicemic, and pneumonic plague. In this study, we compared the conventional counting of bacterial colony forming units (cfu) in the various infected tissues to IVIBB in monitoring Y. pestis dissemination in a mouse model of pneumonic plague. By using a transposon mutagenesis system harboring the luciferase (luc) gene, we screened approximately 4000 clones and obtained a fully virulent, luc-positive Y. pestis CO92 (Y. pestis-luc2) reporter strain in which transposition occurred within the largest pMT1 plasmid which possesses murine toxin and capsular antigen encoding genes. The aforementioned reporter strain and the wild-type CO92 exhibited similar growth curves, formed capsule based on immunofluorescence microscopy and flow cytometry, and had a similar LD50. Intranasal infection of mice with 15 LD50 of CO92-luc2 resulted in animal mortality by 72 h, and an increasing number of bioluminescent bacteria were observed in various mouse organs over a 24–72 h period when whole animals were imaged. However, following levofloxacin treatment (10 mg/kg/day) for 6 days 24 h post infection, no luminescence was observed after 72 h of infection, indicating that the tested antimicrobial killed bacteria preventing their detection in host peripheral tissues. Overall, we demonstrated that IVIBB is an effective and non-invasive way of monitoring bacterial dissemination in animals following pneumonic plague having strong correlation with cfu, and our reporter CO92-luc2 strain can be employed as a useful tool to monitor the efficacy of

  4. Belowground plant development measured with magnetic resonance imaging (MRI): exploiting the potential for non-invasive trait quantification using sugar beet as a proxy

    PubMed Central

    Metzner, Ralf; van Dusschoten, Dagmar; Bühler, Jonas; Schurr, Ulrich; Jahnke, Siegfried

    2014-01-01

    Both structural and functional properties of belowground plant organs are critical for the development and yield of plants but, compared to the shoot, much more difficult to observe due to soil opacity. Many processes concerning the belowground plant performance are not fully understood, in particular spatial and temporal dynamics and their interrelation with environmental factors. We used Magnetic Resonance Imaging (MRI) as a noninvasive method to evaluate which traits can be measured when a complex plant organ is monitored in-vivo while growing in the soil. We chose sugar beet (Beta vulgaris ssp. vulgaris) as a model system. The beet consists mainly of root tissues, is rather complex regarding tissue structure and responses to environmental factors, and thereby a good object to test the applicability of MRI for 3D phenotyping approaches. Over a time period of up to 3 months, traits such as beet morphology or anatomy were followed in the soil and the effect of differently sized pots on beet fresh weight calculated from MRI data was studied. There was a clear positive correlation between the pot size and the increase in fresh weight of a sugar beet over time. Since knowledge of the development of internal beet structures with several concentric cambia, vascular and parenchyma rings is still limited, we consecutively acquired 3D volumetric images on individual plants using the MRI contrast parameter T2 to map the development of rings at the tissue level. This demonstrates that MRI provides versatile protocols to non-invasively measure plant traits in the soil. It opens new avenues to investigate belowground plant performance under adverse environmental conditions such as drought, nutrient shortage, or soil compaction to seek for traits of belowground organs making plants more resilient to stress. PMID:25278947

  5. A non-invasive in vivo imaging system to study dissemination of bioluminescent Yersinia pestis CO92 in a mouse model of pneumonic plague.

    PubMed

    Sha, Jian; Rosenzweig, Jason A; Kirtley, Michelle L; van Lier, Christina J; Fitts, Eric C; Kozlova, Elena V; Erova, Tatiana E; Tiner, Bethany L; Chopra, Ashok K

    2013-02-01

    The gold standard in microbiology for monitoring bacterial dissemination in infected animals has always been viable plate counts. This method, despite being quantitative, requires sacrificing the infected animals. Recently, however, an alternative method of in vivo imaging of bioluminescent bacteria (IVIBB) for monitoring microbial dissemination within the host has been employed. Yersinia pestis is a Gram-negative bacterium capable of causing bubonic, septicemic, and pneumonic plague. In this study, we compared the conventional counting of bacterial colony forming units (cfu) in the various infected tissues to IVIBB in monitoring Y. pestis dissemination in a mouse model of pneumonic plague. By using a transposon mutagenesis system harboring the luciferase (luc) gene, we screened approximately 4000 clones and obtained a fully virulent, luc-positive Y. pestis CO92 (Y. pestis-luc2) reporter strain in which transposition occurred within the largest pMT1 plasmid which possesses murine toxin and capsular antigen encoding genes. The aforementioned reporter strain and the wild-type CO92 exhibited similar growth curves, formed capsule based on immunofluorescence microscopy and flow cytometry, and had a similar LD(50). Intranasal infection of mice with 15 LD(50) of CO92-luc2 resulted in animal mortality by 72 h, and an increasing number of bioluminescent bacteria were observed in various mouse organs over a 24-72 h period when whole animals were imaged. However, following levofloxacin treatment (10 mg/kg/day) for 6 days 24 h post infection, no luminescence was observed after 72 h of infection, indicating that the tested antimicrobial killed bacteria preventing their detection in host peripheral tissues. Overall, we demonstrated that IVIBB is an effective and non-invasive way of monitoring bacterial dissemination in animals following pneumonic plague having strong correlation with cfu, and our reporter CO92-luc2 strain can be employed as a useful tool to monitor the efficacy

  6. Non-invasive high-resolution tracking of human neuronal pathways: diffusion tensor imaging at 7T with 1.2 mm isotropic voxel size

    NASA Astrophysics Data System (ADS)

    Lützkendorf, Ralf; Hertel, Frank; Heidemann, Robin; Thiel, Andreas; Luchtmann, Michael; Plaumann, Markus; Stadler, Jörg; Baecke, Sebastian; Bernarding, Johannes

    2013-03-01

    Diffusion tensor imaging (DTI) allows characterizing and exploiting diffusion anisotropy effects, thereby providing important details about tissue microstructure. A major application in neuroimaging is the so-called fiber tracking where neuronal connections between brain regions are determined non-invasively by DTI. Combining these neural pathways within the human brain with the localization of activated brain areas provided by functional MRI offers important information about functional connectivity of brain regions. However, DTI suffers from severe signal reduction due to the diffusion-weighting. Ultra-high field (UHF) magnetic resonance imaging (MRI) should therefore be advantageous to increase the intrinsic signal-to-noise ratio (SNR). This in turn enables to acquire high quality data with increased resolution, which is beneficial for tracking more complex fiber structures. However, UHF MRI imposes some difficulties mainly due to the larger B1 inhomogeneity compared to 3T MRI. We therefore optimized the parameters to perform DTI at a 7 Tesla whole body MR scanner equipped with a high performance gradient system and a 32-channel head receive coil. A Stesjkal Tanner spin-echo EPI sequence was used, to acquire 110 slices with an isotropic voxel-size of 1.2 mm covering the whole brain. 60 diffusion directions were scanned which allows calculating the principal direction components of the diffusion vector in each voxel. The results prove that DTI can be performed with high quality at UHF and that it is possible to explore the SNT benefit of the higher field strength. Combining UHF fMRI data with UHF DTI results will therefore be a major step towards better neuroimaging methods.

  7. An advanced design of non-radioactive image capturing and management system for applications in non-invasive skin disorder diagnosis

    NASA Astrophysics Data System (ADS)

    Liu, Carol Y. B.; Luk, David C. K.; Zhou, Kany S. Y.; So, Bryan M. K.; Louie, Derek C. H.

    2015-03-01

    Due to the increasing incidences of malignant melanoma, there is a rising demand for assistive technologies for its early diagnosis and improving the survival rate. The commonly used visual screening method is with limited accuracy as the early phase of melanoma shares many clinical features with an atypical nevus, while conventional dermoscopes are not user-friendly in terms of setup time and operations. Therefore, the development of an intelligent and handy system to assist the accurate screening and long-term monitoring of melanocytic skin lesions is crucial for early diagnosis and prevention of melanoma. In this paper, an advanced design of non-invasive and non-radioactive dermoscopy system was reported. Computer-aided simulations were conducted for optimizing the optical design and uniform illumination distribution. Functional prototype and the software system were further developed, which could enable image capturing at 10x amplified and general modes, convenient data transmission, analysis of dermoscopic features (e.g., asymmetry, border irregularity, color, diameter and dermoscopic structure) for assisting the early detection of melanoma, extract patient information (e.g. code, lesion location) and integrate with dermoscopic images, thus further support long term monitoring of diagnostic analysis results. A clinical trial study was further conducted on 185 Chinese children (0-18 years old). The results showed that for all subjects, skin conditions diagnosed based on the developed system accurately confirmed the diagnoses by conventional clinical procedures. Besides, clinical analysis on dermoscopic features and a potential standard approach by the developed system to support identifying specific melanocytic patterns for dermoscopic examination in Chinese children were also reported.

  8. Non-invasive ventilation.

    PubMed Central

    Spence, D.

    1996-01-01

    Nasal intermittent positive pressure ventilation is an effective treatment for nocturnal hypoventilation secondary to chest wall deformity or respiratory muscle weakness. Physicians should be aware that, in these groups of patients, disabling breathlessness can be alleviated and established cor pulmonale reversed by the technique. Images Figure 1 Figure 2 Figure 3 PMID:8949588

  9. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    SciTech Connect

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-02-06

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure vari-ations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagran-gian tracking approach were used to model respiratory airflows and aerosol dynamics. Respira-tions of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug de-livery protocol.

  10. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    SciTech Connect

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug de- livery protocol.

  11. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    PubMed Central

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol. PMID:25767612

  12. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    DOE PAGES

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; ...

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treatmore » the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 μm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.« less

  13. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    SciTech Connect

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 μm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.

  14. Threshold contrast detail detectability measurement of the fluoroscopic image quality of a dynamic solid-state digital x-ray image detector.

    PubMed

    Davies, A G; Cowen, A R; Kengyelics, S M; Bury, R F; Bruijns, T J

    2001-01-01

    Solid-state digital x-ray imaging detectors of flat-panel construction will play an increasingly important role in future medical imaging facilities. Solid-state detectors that will support both dynamic (including fluoroscopic) and radiographic image recording are under active development. The image quality of an experimental solid-state digital x-ray image detector operating in a continuous fluoroscopy mode has been investigated. The threshold contrast detail detectability (TCDD) technique was used to compare the fluoroscopic imaging performance of an experimental dynamic solid-state digital x-ray image detector with that of a reference image intensifier television (IITV) fluoroscopy system. The reference system incorporated Plumbicon TV. Results were presented as a threshold detection index, or H(T)(A), curves. Measurements were made over a range of mean entrance air kerma (EAK) rates typically used in conventional IITV fluoroscopy. At the upper and mid EAK rate range (440 and 220 nGy/s) the solid-state detector outperformed the reference IITV fluoroscopy system as measured by TCDD performance. At the lowest measured EAK rate (104 nGy/s), the solid-state detector produces slightly inferior TCDD performance compared with the reference system. Although not statistically significant at this EAK rate, the difference will increase as EAK is lowered further. Overall the TCDD results and early clinical experiences support the proposition that a current design of dynamic solid-state detector produces image quality competitive with that of modern IITV fluoroscopy systems. These findings encourage the development of compact and versatile universal x-ray imaging systems based upon solid-state detector technology to support R & F and vascular/interventional applications.

  15. Non-invasive Mapping of Cardiac Arrhythmias.

    PubMed

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome).

  16. Non-invasive hemoglobin monitoring.

    PubMed

    Joseph, Bellal; Haider, Ansab; Rhee, Peter

    2016-09-01

    Technology has transformed the practice of medicine and surgery in particular over the last several decades. This change in practice has allowed diagnostic and therapeutic tests to be performed less invasively. Hemoglobin monitoring remains one of the most commonly performed diagnostic tests in the United States. Recently, non-invasive hemoglobin monitoring technology has gained popularity. The aim of this article is to review the principles of how this technology works, pros and cons, and the implications of non-invasive hemoglobin technology particularly in trauma surgery.

  17. Non-Invasive Imaging of Phosphoinositide-3-Kinase-Catalytic-Subunit-Alpha (PIK3CA) Promoter Modulation in Small Animal Models

    PubMed Central

    Gaikwad, Snehal M.; Gunjal, Lata; Junutula, Anitha R.; Astanehe, Arezoo; Gambhir, Sanjiv Sam; Ray, Pritha

    2013-01-01

    Activation of the PI3K/Akt pathway, a critical step for survival in cancer cells is often associated with decreased sensitivity to several chemotherapeutic drugs. PIK3CA gene amplification is observed in 16–24% of epithelial ovarian cancer (EOC) patients in conjunction with p53 mutations. A 900 bp long PIK3CA promoter is shown to be negatively regulated by p53 in ovarian surface epithelial cells but the consequence of chemotherapeutic drug treatments on this promoter in ovarian cancer cells is largely unknown. We aim to study the modulation of this promoter by cisplatin using an improved fusion reporter in ovarian cancer cells and tumor xenografts by non-invasive imaging approach. A PIK3CA sensor was developed using a bi-fusion reporter from a newly constructed library of bi- and tri-fusion vectors comprising of two mutant far red fluorescent proteins (mcherry/mch and tdTomato/tdt), a mutant firefly luciferase (fluc2), and a PET reporter protein (ttk). In vivo imaging of mice implanted with 293T cells transiently expressing these bi- and tri-fusion reporters along with respective controls revealed comparable activity of each reporter in the fusion background and fluc2-tdt as the most sensitive one. Repression of the PIK3CA sensor by drugs was inversely proportional to cellular p53 level in a germline (PA1) and in an EOC (A2780) cell line but not in a p53 deficient EOC (SKOV3) cell line. Bioluminescence imaging of tumor xenografts stably expressing the PIK3CA sensor in PA1 and A2780 cells exhibited attenuating activity without any change in SKOV3 tumors expressing the PIK3CA sensor after cisplatin treatment. Sequential mutation at p53 binding sites showed gradual increase in promoter activity and decreased effects of the drugs. These newly developed PIK3CA-fluc2-tdt and the mutant reporter sensors thus would be extremely useful for screening new drugs and for functional assessment of PIK3CA expression from intact cells to living subjects. PMID:23393606

  18. Use of Non-Invasive Phase Contrast Magnetic Resonance Imaging for Estimation of Atrial Septal Defect Size and Morphology: A Comparison with Transesophageal Echo

    SciTech Connect

    Piaw, Chin Sze; Kiam, Ong Tiong; Rapaee, Annuar Khoon, Liew Chee; Bang, Liew Houng; Ling, Chan Wei; Samion, Hasri; Hian, Sim Kui

    2006-04-15

    Background: Transesophageal echocardiography (TEE) is a trusted method of sizing atrial septal defect (ASD) prior to percutaneous closure but is invasive, uncomfortable, and may carry a small risk of morbidity and mortality. Magnetic resonance imaging (MRI) may be useful non-invasive alternative in such patients who refuse or are unable to tolerate TEE and may provide additional information on the shape of the A0SD. Purpose: To validate the accuracy of ASD sizing by MRI compared with TEE.Method: Twelve patients (mean age 30 years; range 11-60 years) scheduled for ASD closure underwent TEE, cine balanced fast field echo MRI (bFFE-MRI) in four-chamber and sagittal views and phase-contrast MRI (PC-MRI) with reconstruction using the two orthogonal planes of T2-weighted images as planning. The average of the three longest measurements for all imaging modalities was calculated for each patient. Results: Mean maximum ASD length on TEE was 18.8 {+-} 4.6 mm, mean length by bFFE-MRI was 20.0 {+-} 5.0 mm, and mean length by PC-MRI was 18.3 {+-} 3.6 mm. The TEE measurement was significantly correlated with the bFFE-MRI and PC-MRI measurements (Pearson r = 0.69, p = 0.02 and r = 0.59, p = 0.04, respectively). The mean difference between TEE and bFFE-MRI measurements was -1.2mm (95% CI: -3.7, 1.3) and between TEE and PC-MRI was 0.5 mm (95% CI: -1.9, 2.9). Bland-Altman analysis also determined general agreement between both MRI methods and TEE. The ASDs were egg-shaped in two cases, circular in 1 patient and oval in the remaining patients. Conclusion: ASD sizing by MRI using bFFE and phase-contrast protocols correlated well with TEE estimations. PC-MRI provided additional information on ASD shapes and proximity to adjacent structures.

  19. Investigation of first ray mobility during gait by kinematic fluoroscopic imaging-a novel method

    PubMed Central

    2012-01-01

    Background It is often suggested that sagittal instability at the first tarso-metatarsal joint level is a primary factor for hallux valgus and that sagittal instability increases with the progression of the deformity. The assessment of the degree of vertical instability is usually made by clinical evaluation while any measurements mostly refer to a static assessment of medial ray mobility (i.e. the plantar/dorsal flexion in the sagittal plane). Testing methods currently available cannot attribute the degree of mobility to the corresponding anatomical joints making up the medial column of the foot. The aim of this study was to develop a technique which allows for a quantification of the in-vivo sagittal mobility of the joints of the medial foot column during the roll-over process under full weight bearing. Methods Mobility of first ray bones was investigated by dynamic distortion-free fluoroscopy (25 frames/s) of 14 healthy volunteers and 8 patients with manifested clinical instability of the first ray. A CAD-based evaluation method allowed the determination of mobility and relative displacements and rotations of the first ray bones within the sagittal plane during the stance phase of gait. Results Total flexion of the first ray was found to be 13.63 (SD 6.14) mm with the healthy volunteers and 13.06 (SD 8.01) mm with the patients (resolution: 0.245 mm/pixel). The dorsiflexion angle was 5.27 (SD 2.34) degrees in the healthy volunteers and increased to 5.56 (SD 3.37) degrees in the patients. Maximum rotations were found at the naviculo-cuneiform joints and least at the first tarso-metatarsal joint level in both groups. Conclusions Dynamic fluoroscopic assessment has been shown to be a valuable tool for characterisation of the kinematics of the joints of the medial foot column during gait. A significant difference in first ray flexion and angular rotation between the patients and healthy volunteers however could not be found. PMID:22316084

  20. 21 CFR 1020.32 - Fluoroscopic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... fluoroscopic image receptor using photographic film or a video camera when the x-ray source is operated in a...-hold feature that are not recorded. (C) When a mode of operation has an optional high-level control...

  1. The Non-Invasive Functional Tissue Characterization for Arteriosclerosis by Artery Wall Motion Analysis with Time Series High-Speed Echo Images and Continuous Spygmo-Manometer

    DTIC Science & Technology

    2007-11-02

    Abstract- The evaluation method of arteriosclerosis has been established, but most of them are invasive way. In late years, non-invasive diagnostic...method for arteriosclerosis can be done by the diagnosis with high resolution echography. However, even this new diagnostic method can not diagnose...until beginning the morphologic changes of the arteries by stenosis. There is little value even if it could be detected the arteriosclerosis after the

  2. Non-invasive determination of coupled motion of the scapula and humerus--an in-vitro validation.

    PubMed

    Massimini, Daniel F; Warner, Jon J P; Li, Guoan

    2011-02-03

    Measuring the motion of the scapula and humerus with sub-millimeter levels of accuracy in six-degrees-of-freedom (6-DOF) is a challenging problem. The current methods to measure shoulder joint motion via the skin do not produce clinically significant levels of accuracy. Thus, the purpose of this study was to validate a non-invasive markerless dual fluoroscopic imaging system (DFIS) model-based tracking technique for measuring dynamic in-vivo shoulder kinematics. Our DFIS tracks the positions of bones based on their projected silhouettes to contours on recorded pairs of fluoroscopic images. For this study, we compared markerlessly tracking the bones of the scapula and humerus to track them with implanted titanium spheres using a radiostereometric analysis (RSA) while manually manipulating a cadaver specimen's arms. Additionally, we report the repeatability of the DFIS to track the scapula and humerus during dynamic shoulder motion. The difference between the markerless model-based tracking technique and the RSA was ±0.3 mm in translation and ±0.5° in rotation. Furthermore, the repeatability of the markerless DFIS model-based tracking technique for the scapula and humerus was ±0.2 mm and ±0.4°, respectively. The model-based tracking technique achieves an accuracy that is similar to an invasive RSA tracking technique and is highly suited for non-invasively studying the in-vivo motion of the shoulder. This technique could be used to investigate the scapular and humeral biomechanics in both healthy individuals and in patients with various pathologies under a variety of dynamic shoulder motions encountered during the activities of daily living.

  3. Three-dimensional kinematic estimation of mobile-bearing total knee arthroplasty from x-ray fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Yamazaki, Takaharu; Futai, Kazuma; Tomita, Tetsuya; Sato, Yoshinobu; Yoshikawa, Hideki; Tamura, Shinichi; Sugamoto, Kazuomi

    2011-03-01

    To achieve 3D kinematic analysis of total knee arthroplasty (TKA), 2D/3D registration techniques, which use X-ray fluoroscopic images and computer-aided design (CAD) model of the knee implant, have attracted attention in recent years. These techniques could provide information regarding the movement of radiopaque femoral and tibial components but could not provide information of radiolucent polyethylene insert, because the insert silhouette on X-ray image did not appear clearly. Therefore, it was difficult to obtain 3D kinemaitcs of polyethylene insert, particularly mobile-bearing insert that move on the tibial component. This study presents a technique and the accuracy for 3D kinematic analysis of mobile-bearing insert in TKA using X-ray fluoroscopy, and finally performs clinical applications. For a 3D pose estimation technique of the mobile-bearing insert in TKA using X-ray fluoroscopy, tantalum beads and CAD model with its beads are utilized, and the 3D pose of the insert model is estimated using a feature-based 2D/3D registration technique. In order to validate the accuracy of the present technique, experiments including computer simulation test were performed. The results showed the pose estimation accuracy was sufficient for analyzing mobile-bearing TKA kinematics (the RMS error: about 1.0 mm, 1.0 degree). In the clinical applications, seven patients with mobile-bearing TKA in deep knee bending motion were studied and analyzed. Consequently, present technique enables us to better understand mobile-bearing TKA kinematics, and this type of evaluation was thought to be helpful for improving implant design and optimizing TKA surgical techniques.

  4. Non-invasive evaluation of culprit lesions by PET imaging: shifting the clinical paradigm away from resultant anatomy toward causative physiology.

    PubMed

    Caobelli, Federico; Bengel, Frank M

    2014-12-01

    Although coronary angiography is the gold standard for assessing coronary artery disease (CAD), there is at best a weak correlation between degree of stenosis and the risk of developing cardiac events. Plaque rupture is the most common type of plaque complication, accounting for about 70% of fatal acute myocardial infarctions or sudden coronary deaths. Recently, the feasibility of (18)F-fluoride PET/CT in the evaluation of atherosclerotic lesions was assessed. Radionuclide techniques allow non-invasive biologic assessment of atherosclerotic plaques. This may help to further shift the clinical paradigm in coronary disease away from anatomy toward causative physiology and biology.

  5. Non-invasive evaluation of culprit lesions by PET imaging: shifting the clinical paradigm away from resultant anatomy toward causative physiology

    PubMed Central

    Bengel, Frank M.

    2014-01-01

    Although coronary angiography is the gold standard for assessing coronary artery disease (CAD), there is at best a weak correlation between degree of stenosis and the risk of developing cardiac events. Plaque rupture is the most common type of plaque complication, accounting for about 70% of fatal acute myocardial infarctions or sudden coronary deaths. Recently, the feasibility of 18F-fluoride PET/CT in the evaluation of atherosclerotic lesions was assessed. Radionuclide techniques allow non-invasive biologic assessment of atherosclerotic plaques. This may help to further shift the clinical paradigm in coronary disease away from anatomy toward causative physiology and biology. PMID:25610799

  6. Safety and efficacy of dalcetrapib on atherosclerotic disease using novel non-invasive multimodality imaging (dal-PLAQUE): a randomised clinical trial

    PubMed Central

    Fayad, Zahi A; Mani, Venkatesh; Woodward, Mark; Kallend, David; Abt, Markus; Burgess, Tracy; Fuster, Valentin; Ballantyne, Christie M; Stein, Evan A; Tardif, Jean-Claude; Rudd, James H F; Farkouh, Michael E; Tawakol, Ahmed

    2014-01-01

    Summary Background Dalcetrapib modulates cholesteryl ester transfer protein (CETP) activity to raise high-density lipoprotein cholesterol (HDL-C). After the failure of torcetrapib it was unknown if HDL produced by interaction with CETP had pro-atherogenic or pro-inflammatory properties. dal-PLAQUE is the first multicentre study using novel non-invasive multimodality imaging to assess structural and inflammatory indices of atherosclerosis as primary endpoints. Methods In this phase 2b, double-blind, multicentre trial, patients (aged 18–75 years) with, or with high risk of, coronary heart disease were randomly assigned (1:1) to dalcetrapib 600 mg/day or placebo for 24 months. Randomisation was done with a computer-generated randomisation code and was stratified by centre. Patients and investigators were masked to treatment. Coprimary endpoints were MRI-assessed indices (total vessel area, wall area, wall thickness, and normalised wall index [average carotid]) after 24 months and 18F-fluorodeoxyglucose (18F-FDG) PET/CT assessment of arterial inflammation within an index vessel (right carotid, left carotid, or ascending thoracic aorta) after 6 months, with no-harm boundaries established before unblinding of the trial. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00655473. Findings 189 patients were screened and 130 randomly assigned to placebo (66 patients) or dalcetrapib (64 patients). For the coprimary MRI and PET/CT endpoints, CIs were below the no-harm boundary or the adverse change was numerically lower in the dalcetrapib group than in the placebo group. MRI-derived change in total vessel area was reduced in patients given dalcetrapib compared with those given placebo after 24 months; absolute change from baseline relative to placebo was −4·01 mm2 (90% CI −7·23 to −0·80; nominal p=0·04). The PET/CT measure of index vessel most-diseased-segment target-to-background ratio (TBR) was not different between groups

  7. Fluoroscopic x-ray imaging with amorphous silicon thin-film arrays

    NASA Astrophysics Data System (ADS)

    Schiebel, Ulrich W.; Conrads, Norbert; Jung, Norbert; Weibrecht, Martin; Wieczorek, Herfried K.; Zaengel, Thomas T.; Powell, M. J.; French, I. D.; Glasse, C.

    1994-05-01

    The dream of an all-solid state large area x-ray image sensor with digital readout and full dynamic performance will most probably find a first realization in 2D thin-film amorphous silicon arrays. In this paper we address in particular the evaluation of the limits of the signal/noise ratio in this concept. Using small prototype detectors measurements of MTF and noise power spectra have been made as a function of x-ray dose. The results are given in terms of the detective quantum efficiency as a function of dose and spatial frequency. We further present an analysis of the different noise sources and their dependence on the detector parameters, and we provide estimates on the maximum signals that may be achieved per unit dose. The intrinsic lag of the amorphous silicon photodiodes causes a second problem area with this type of x-ray detectors. Especially in radiography/fluoroscopy mixed applications, memory effects may not be negligible.

  8. Special designed RF-antenna with integrated non-invasive carbon electrodes for simultaneous magnetic resonance imaging and electroencephalography acquisition at 7T.

    PubMed

    Van Audekerkea, J; Peeters, R; Verhoye, M; Sijbers, J; Van der Linden, A

    2000-09-01

    The construction of a high quality MR RF-antenna with incorporated EEG electrodes for simultaneous MRI and EEG acquisition is presented. The antenna comprises an active decoupled surface coil for receiving the MR signal and a whole body coil for transmitting the excitation RF pulses. The surface coil offers a high signal-to-noise ratio required for fMRI application and the whole body coil has a good B(1) excitation profile, which enables the application of homogeneous RF pulses. Non-invasive carbon electrodes are used in order to minimise the magnetic susceptibility artefacts that occur upon application of conductive materials. This dedicated set-up is compared to a standard set-up being a linear birdcage coil and commercially available Ag/AgCl electrodes. As the acquired EEG signals are heavily disturbed by the gradient switching, intelligent filtering is applied to obtain a clean EEG signal.

  9. Investigation on effect of image lag in fluoroscopic images obtained with a dynamic flat-panel detector (FPD) on accuracy of target tracking in radiotherapy.

    PubMed

    Tanaka, Rie; Ichikawa, Katsuhiro; Mori, Shinichiro; Dobashi, Suguru; Kumagai, Motoki; Kawashima, Hiroki; Minohara, Shinichi; Sanada, Sigeru

    2010-01-01

    Real-time tumor tracking in external radiotherapy can be achieved by diagnostic (kV) X-ray imaging with a dynamic flat-panel detector (FPD). The purpose of this study was to address image lag in target tracking and its influence on the accuracy of tumor tracking. Fluoroscopic images were obtained using a direct type of dynamic FPD. Image lag properties were measured without test devices according to IEC 62220-1. Modulation transfer function (MTF) and profile curves were measured on the edges of a moving tungsten plate at movement rate of 10 and 20 mm/s, covering lung tumor movement of normal breathing. A lung tumor and metal sphere with blurred edge due to image lag was simulated using the results and then superimposed on breathing chest radiographs of a patient. The moving target with and without image lag was traced using a template-matching technique. In the results, the image lag for the first frame after X-ray cutoff was 2.0% and decreased to less than 0.1% in the fifth frame. In the measurement of profile curves on the edges of static and moving tungsten material plates, the effect of image lag was seen as blurred edges of the plate. The blurred edges of a moving target were indicated as reduction of MTF. However, the target could be traced within an error of ± 5 mm. The results indicated that there was no effect of image lag on target tracking in usual breathing speed in a radiotherapy situation.

  10. Non-invasive Evaluation for Epilepsy Surgery

    PubMed Central

    IWASAKI, Masaki; JIN, Kazutaka; NAKASATO, Nobukazu; TOMINAGA, Teiji

    2016-01-01

    Epilepsy surgery is aimed to remove the brain tissues that are indispensable for generating patient’s epileptic seizures. There are two purposes in the pre-operative evaluation: localization of the epileptogenic zone and localization of function. Surgery is planned to remove possible epileptogenic zone while preserving functional area. Since no single diagnostic modality is superior to others in identifying and localizing the epileptogenic zone, multiple non-invasive evaluations are performed to estimate the location of the epileptogenic zone after concordance between evaluations. Essential components of non-invasive pre-surgical evaluation of epilepsy include detailed clinical history, long-term video-electroencephalography monitoring, epilepsy-protocol magnetic resonance imaging (MRI), and neuropsychological testing. However, a significant portion of drug-resistant epilepsy is associated with no or subtle MRI lesions or with ambiguous electro-clinical signs. Additional evaluations including fluoro-deoxy glucose positron emission tomography (FDG-PET), magnetoencephalography and ictal single photon emission computed tomography can play critical roles in planning surgery. FDG-PET should be registered on three-dimensional MRI for better detection of focal cortical dysplasia. All diagnostic tools are complementary to each other in defining the epileptogenic zone, so that it is always important to reassess the data based on other results to pick up or confirm subtle abnormalities. PMID:27627857

  11. 21 CFR 1020.32 - Fluoroscopic equipment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... images from the fluoroscopic image receptor, except computed tomography x-ray systems manufactured on or... section of the useful beam at any SID. The x-ray tube used for fluoroscopy shall not produce x-rays unless... manufactured after February 25, 1978, when the angle between the image receptor and the beam axis of the...

  12. 21 CFR 1020.32 - Fluoroscopic equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... images from the fluoroscopic image receptor, except computed tomography x-ray systems manufactured on or... section of the useful beam at any SID. The x-ray tube used for fluoroscopy shall not produce x-rays unless... manufactured after February 25, 1978, when the angle between the image receptor and the beam axis of the...

  13. 21 CFR 1020.32 - Fluoroscopic equipment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... images from the fluoroscopic image receptor, except computed tomography x-ray systems manufactured on or... section of the useful beam at any SID. The x-ray tube used for fluoroscopy shall not produce x-rays unless... manufactured after February 25, 1978, when the angle between the image receptor and the beam axis of the...

  14. 21 CFR 1020.32 - Fluoroscopic equipment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... images from the fluoroscopic image receptor, except computed tomography x-ray systems manufactured on or... section of the useful beam at any SID. The x-ray tube used for fluoroscopy shall not produce x-rays unless... manufactured after February 25, 1978, when the angle between the image receptor and the beam axis of the...

  15. An Open Source Image Processing Method to Quantitatively Assess Tissue Growth after Non-Invasive Magnetic Resonance Imaging in Human Bone Marrow Stromal Cell Seeded 3D Polymeric Scaffolds

    PubMed Central

    Leferink, Anne M.; Fratila, Raluca M.; Koenrades, Maaike A.; van Blitterswijk, Clemens A.; Velders, Aldrik; Moroni, Lorenzo

    2014-01-01

    Monitoring extracellular matrix (ECM) components is one of the key methods used to determine tissue quality in three-dimensional (3D) scaffolds for regenerative medicine and clinical purposes. This is even more important when multipotent human bone marrow stromal cells (hMSCs) are used, as it could offer a method to understand in real time the dynamics of stromal cell differentiation and eventually steer it into the desired lineage. Magnetic Resonance Imaging (MRI) is a promising tool to overcome the challenge of a limited transparency in opaque 3D scaffolds. Technical limitations of MRI involve non-uniform background intensity leading to fluctuating background signals and therewith complicating quantifications on the retrieved images. We present a post-imaging processing sequence that is able to correct for this non-uniform background intensity. To test the processing sequence we investigated the use of MRI for in vitro monitoring of tissue growth in three-dimensional poly(ethylene oxide terephthalate)–poly(butylene terephthalate) (PEOT/PBT) scaffolds. Results showed that MRI, without the need to use contrast agents, is a promising non-invasive tool to quantitatively monitor ECM production and cell distribution during in vitro culture in 3D porous tissue engineered constructs. PMID:25502022

  16. An open source image processing method to quantitatively assess tissue growth after non-invasive magnetic resonance imaging in human bone marrow stromal cell seeded 3D polymeric scaffolds.

    PubMed

    Leferink, Anne M; Fratila, Raluca M; Koenrades, Maaike A; van Blitterswijk, Clemens A; Velders, Aldrik; Moroni, Lorenzo

    2014-01-01

    Monitoring extracellular matrix (ECM) components is one of the key methods used to determine tissue quality in three-dimensional (3D) scaffolds for regenerative medicine and clinical purposes. This is even more important when multipotent human bone marrow stromal cells (hMSCs) are used, as it could offer a method to understand in real time the dynamics of stromal cell differentiation and eventually steer it into the desired lineage. Magnetic Resonance Imaging (MRI) is a promising tool to overcome the challenge of a limited transparency in opaque 3D scaffolds. Technical limitations of MRI involve non-uniform background intensity leading to fluctuating background signals and therewith complicating quantifications on the retrieved images. We present a post-imaging processing sequence that is able to correct for this non-uniform background intensity. To test the processing sequence we investigated the use of MRI for in vitro monitoring of tissue growth in three-dimensional poly(ethylene oxide terephthalate)-poly(butylene terephthalate) (PEOT/PBT) scaffolds. Results showed that MRI, without the need to use contrast agents, is a promising non-invasive tool to quantitatively monitor ECM production and cell distribution during in vitro culture in 3D porous tissue engineered constructs.

  17. Non-invasive glucose monitor

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2001-01-01

    A non-invasive method for determining blood level of an analyte of interest, such as glucose, comprises: generating an excitation laser beam (e.g., at a wavelength of 700 to 900 nanometers); focusing the excitation laser beam into the anterior chamber of an eye of the subject so that aqueous humor in the anterior chamber is illuminated; detecting (preferably confocally detecting) a Raman spectrum from the illuminated aqueous humor; and then determining the blood glucose level (or the level of another analyte of interest) for the subject from the Raman spectrum. Preferably, the detecting step is followed by the step of subtracting a confounding fluorescence spectrum from the Raman spectrum to produce a difference spectrum; and determining the blood level of the analyte of interest for the subject from that difference spectrum, preferably using linear or nonlinear multivariate analysis such as partial least squares analysis. Apparatus for carrying out the foregoing method is also disclosed.

  18. Non-invasive high resolving power quantum microscope

    NASA Astrophysics Data System (ADS)

    Karmakar, Sanjit; Meyers, Ronald; Shih, Yanhua

    2013-09-01

    The development of a non-invasive high resolving power quantum microscope would further advance progress in research and development in biomedical and biosciences as well as the field of medical technology. Longer wavelengths, i.e visible or near-infrared, provide less invasive impact. On the other hand shorter wavelengths, i.e. UV, can provide better resolving power. That is why the development of a non-invasive high resolving power quantum microscope is critical. In this article, we propose such a microscope by using two-color entangled photon ghost imaging technology.

  19. WE-G-207-06: 3D Fluoroscopic Image Generation From Patient-Specific 4DCBCT-Based Motion Models Derived From Physical Phantom and Clinical Patient Images

    SciTech Connect

    Dhou, S; Cai, W; Hurwitz, M; Rottmann, J; Myronakis, M; Cifter, F; Berbeco, R; Lewis, J; Williams, C; Mishra, P; Ionascu, D

    2015-06-15

    Purpose: Respiratory-correlated cone-beam CT (4DCBCT) images acquired immediately prior to treatment have the potential to represent patient motion patterns and anatomy during treatment, including both intra- and inter-fractional changes. We develop a method to generate patient-specific motion models based on 4DCBCT images acquired with existing clinical equipment and used to generate time varying volumetric images (3D fluoroscopic images) representing motion during treatment delivery. Methods: Motion models are derived by deformably registering each 4DCBCT phase to a reference phase, and performing principal component analysis (PCA) on the resulting displacement vector fields. 3D fluoroscopic images are estimated by optimizing the resulting PCA coefficients iteratively through comparison of the cone-beam projections simulating kV treatment imaging and digitally reconstructed radiographs generated from the motion model. Patient and physical phantom datasets are used to evaluate the method in terms of tumor localization error compared to manually defined ground truth positions. Results: 4DCBCT-based motion models were derived and used to generate 3D fluoroscopic images at treatment time. For the patient datasets, the average tumor localization error and the 95th percentile were 1.57 and 3.13 respectively in subsets of four patient datasets. For the physical phantom datasets, the average tumor localization error and the 95th percentile were 1.14 and 2.78 respectively in two datasets. 4DCBCT motion models are shown to perform well in the context of generating 3D fluoroscopic images due to their ability to reproduce anatomical changes at treatment time. Conclusion: This study showed the feasibility of deriving 4DCBCT-based motion models and using them to generate 3D fluoroscopic images at treatment time in real clinical settings. 4DCBCT-based motion models were found to account for the 3D non-rigid motion of the patient anatomy during treatment and have the potential

  20. Non-Invasive Glucose Measurement

    NASA Astrophysics Data System (ADS)

    Blakley, Daniel

    2010-10-01

    There are two little words, when taken together have great implications: ``What IF'' In the US alone, there are millions who are burdened with diabetes and who must maintain their glucose levels by taking blood samples and having it analyzed. Even though this procedure has improved over time, still it is very intrusive and is a burden to many that must live with it. What if it were not necessary? Although it is current practice to measure glucose levels invasively (using blood samples), it may be possible to measure glucose non-invasively. Although several companies around the world have invested millions of dollars to address this problem, none have been successful thus far. However, there are many methods that hold a potential and many approaches that have not yet been explored. We are working on a review of what has been approached thus far and are entertaining proposals for a combined interdisciplinary approach which combines expertise from bioengineering, physics, and biology. We hope to learn from the unsuccessful attempts of others whilst employing innovative new approaches to this problem.

  1. Preclinical evaluation of destruxin B as a novel Wnt signaling target suppressing proliferation and metastasis of colorectal cancer using non-invasive bioluminescence imaging

    SciTech Connect

    Yeh, Chi-Tai; Rao, Yerra Koteswara; Ye, Min; Wu, Wen-Shi; Chang, Tung-Chen; Wang, Liang-Shun; Wu, Chih-Hsiung; Wu, Alexander T.H.; Tzeng, Yew-Min

    2012-05-15

    In continuation to our studies toward the identification of direct anti-cancer targets, here we showed that destruxin B (DB) from Metarhizium anisopliae suppressed the proliferation and induced cell cycle arrest in human colorectal cancer (CRC) HT29, SW480 and HCT116 cells. Additionally, DB induced apoptosis in HT29 cells by decreased expression level of anti-apoptotic proteins Bcl-2 and Bcl-xL while increased pro-apoptotic Bax. On the other hand, DB attenuated Wnt-signaling by downregulation of β-catenin, Tcf4 and β-catenin/Tcf4 transcriptional activity, concomitantly with decreased expression of β-catenin target genes cyclin D1, c-myc and survivin. Furthermore, DB affected the migratory and invasive ability of HT29 cells through suppressed MMPs-2 and -9 enzymatic activities. We also found that DB targeted the MAPK and/or PI3K/Akt pathway by reduced expression of Akt, IKK-α, JNK, NF-κB, c-Jun and c-Fos while increased that of IκBα. Finally, we demonstrated that DB inhibited tumorigenesis in HT29 xenograft mice using non-invasive bioluminescence technique. Consistently, tumor samples from DB-treated mice demonstrated suppressed expression of β-catenin, cyclin D1, survivin, and endothelial marker CD31 while increased caspase-3 expression. Collectively, our data supports DB as an inhibitor of Wnt/β-catenin/Tcf signaling pathway that may be beneficial in the CRC management. Highlights: ► Destruxin B (DB) inhibited colorectal cancer cells growth and induced apoptosis. ► MAPK and/or PI3K/Akt cascade cooperates in DB induced apoptosis. ► DB affected the migratory and invasive ability of HT29 cells through MMP-9. ► DB attenuated Wnt-signaling components β-catenin, Tcf4. ► DB attenuated cyclin D1, c-myc, survivin and tumorigenesis in HT29 xenograft mice.

  2. Percutaneous Cervical Vertebroplasty in a MultifunctionalImage-Guided Therapy Suite: Hybrid Lateral Approach to C1 andC4 Under CT and Fluoroscopic Guidance

    SciTech Connect

    Huegli, R.W. Schaeren, S.; Jacob, A.L.; Martin, J.B.; Wetzel, S.G.

    2005-06-15

    A 76-year-old patient suffering from two painful osteolytic metastases in C1 and C4 underwent percutaneous vertebroplasty by a hybrid technique in a multi-functional image-guided therapy suite (MIGTS). Two trocars were first placed into the respective bodies of C1 and C4 under fluoroscopic computed tomography guidance using a lateral approach. Thereafter, the patient was transferred on a moving table to the digital subtraction angiography unit in the same room for implant injection. Good pain relief was achieved by this minimally invasive procedure without complications. A hybrid approach for vertebroplasty in a MIGTS appears to be safe and feasible and might be indicated in selected cases for difficult accessible lesions.

  3. Non-invasive physiology in conscious mice.

    PubMed

    Kale, Ajit; Amende, Ivo; Piskorski, Katrina; Chu, Victor; Otero, Jose M; Mueller, Peter; Hampton, Thomas G

    2004-06-01

    Linking gene defect to disease phenotypes in mice has become an essential step in the development of new drugs. Yet, many in vitro and in vivo assays require anaesthetic and surgery or do not reflect physiologically relevant phenomena. The effects of genes or diseases may only become apparent with stressors. Here, we apply non-invasive ECG monitoring and gait imaging systems to describe changes in the electrocardiogram and in gait dynamics resulting from a doubling of the ambulatory speed of mice. We found that B6C3H mice (n = 5) take 3.6 +/- 0.1 strides/second to walk 18cm/second and have a heart rate of 750 +/- 2bpm after 1 minute of walking at this speed. These mice significantly increase stride frequency to 5.2 +/- 0.1 strides/second in order to increase their speed to 36cm/second. The heart rate increased significantly (814 +/- 9bpm, p < 0.05) after trotting at the higher speed for 90 seconds, and the QRS interval duration significantly decreased (9.4 +/- 0.3ms vs. 10.4 +/- 0.3ms, p < 0.05). We discuss the application of the ECG screening and gait imaging systems to mouse models of Duchenne muscular dystrophy, Down syndrome and amyotrophic lateral sclerosis, diseases in humans that are known to affect the heart and neuromuscular systems.

  4. Novel non-invasive distribution measurement of texture profile analysis (TPA) in salmon fillet by using visible and near infrared hyperspectral imaging.

    PubMed

    Wu, Di; Sun, Da-Wen; He, Yong

    2014-02-15

    This study developed a pushbroom visible and near-infrared hyperspectral imaging system in the wavelength range of 400-1758 nm to determine the spatial distribution of texture profile analysis (TPA) parameters of salmon fillets. Six TPA parameters (hardness, adhesiveness, chewiness, springiness, cohesiveness, and gumminess) were analysed. Five spectral features (mean, standard deviation, skew, energy, and entropy) and 22 image texture features obtained from graylevel co-occurrence matrix (GLCM) were extracted from hyperspectral images. Quantitative models were established with the extracted spectral and image texture signatures of samples based on partial least squares regression (PLSR). The results indicated that spectral features had better ability to predict TPA parameters of salmon samples than image texture features, and Spectral Set I (400-1000 nm) performed better than Spectral II (967-1634 nm). On the basis of the wavelengths selected by regression coefficients of PLSR models, instrumental optimal wavelengths (IOW) and predictive optimal wavelengths (POW) were further chosen to reduce the high dimensionality of the hyperspectral image data. Our results show that hyperspectral imaging holds promise as a reliable and rapid alternative to traditional universal testing machines for measuring the spatial distribution of TPA parameters.

  5. Remote Non-invasive Stereoscopic Imaging of Blood Vessels: First In-vivo Results of a New Multispectral Contrast Enhancement Technology

    PubMed Central

    Mastik, F.; Cate, F. J. ten; Neumann, H. A. M.; van der Steen, A. F. W.

    2006-01-01

    We describe a contactless optical technique selectively enhancing superficial blood vessels below variously pigmented intact human skin by combining images in different spectral bands. Two CMOS-cameras, with apochromatic lenses and dual-band LED-arrays, simultaneously streamed Left (L) and Right (R) image data to a dual-processor PC. Both cameras captured color images within the visible range (VIS, 400–780 nm) and grey-scale images within the near infrared range (NIR, 910–920 nm) by sequentially switching between LED-array emission bands. Image-size-settings of 1280 × 1024 for VIS & 640 × 512 for NIR produced 12 cycles/s (1 cycle = 1 VIS L&R-pair + 1 NIR L&R-pair). Decreasing image-size-settings (640 × 512 for VIS and 320 × 256 for NIR) increased camera-speed to 25 cycles/s. Contrasts from below the tissue surface were algorithmically distinguished from surface shadows, reflections, etc. Thus blood vessels were selectively enhanced and back-projected into the stereoscopic VIS-color-image using either a 3D-display or conventional shutter glasses. As a first usability reconnaissance we applied this custom-built mobile stereoscopic camera for several clinical settings: • blood withdrawal; • vein inspection in dark skin; • vein detection through iodide; • varicose vein and nevi pigmentosum inspection. Our technique improves blood vessel visualization compared to the naked eye, and supports depth perception. PMID:17048103

  6. Radiation injuries after fluoroscopic procedures.

    PubMed

    Mettler, Fred A; Koenig, Titus R; Wagner, Louis K; Kelsey, Charles A

    2002-10-01

    Fluoroscopically guided diagnostic and interventional procedures have become much more commonplace over the last decade. Current fluoroscopes are easily capable of producing dose rates in the range of 0.2 Gy (20 rads) per minute. The dose rate often changes dramatically with patient positioning and size. Most machines currently in use have no method to display approximate patient dose other than the rough surrogate of total fluoroscopy time. This does not include patient dose incurred during fluorography (serial imaging or cine runs), which can be considerably greater than dose during fluoroscopy. There have been over 100 cases of documented radiation skin and underlying tissue injury, a large portion of which resulted in dermal necrosis. The true number of injuries is undoubtedly much higher. The highest dose procedures are complex interventions such as those involving percutaneous angioplasties, stent placements, embolizations, and TIPS. In some cases skin doses have been in excess of 60 Gy (6000 rads). In many instances the procedures have been performed by physicians with little training in radiation effects, little appreciation of the radiation injuries that are possible or the strategies that could have been used to reduce both patient and staff doses. Almost all of the severe injuries that have occurred were avoidable.

  7. Non-invasive breast biopsy method using GD-DTPA contrast enhanced MRI series and F-18-FDG PET/CT dynamic image series

    NASA Astrophysics Data System (ADS)

    Magri, Alphonso William

    This study was undertaken to develop a nonsurgical breast biopsy from Gd-DTPA Contrast Enhanced Magnetic Resonance (CE-MR) images and F-18-FDG PET/CT dynamic image series. A five-step process was developed to accomplish this. (1) Dynamic PET series were nonrigidly registered to the initial frame using a finite element method (FEM) based registration that requires fiducial skin markers to sample the displacement field between image frames. A commercial FEM package (ANSYS) was used for meshing and FEM calculations. Dynamic PET image series registrations were evaluated using similarity measurements SAVD and NCC. (2) Dynamic CE-MR series were nonrigidly registered to the initial frame using two registration methods: a multi-resolution free-form deformation (FFD) registration driven by normalized mutual information, and a FEM-based registration method. Dynamic CE-MR image series registrations were evaluated using similarity measurements, localization measurements, and qualitative comparison of motion artifacts. FFD registration was found to be superior to FEM-based registration. (3) Nonlinear curve fitting was performed for each voxel of the PET/CT volume of activity versus time, based on a realistic two-compartmental Patlak model. Three parameters for this model were fitted; two of them describe the activity levels in the blood and in the cellular compartment, while the third characterizes the washout rate of F-18-FDG from the cellular compartment. (4) Nonlinear curve fitting was performed for each voxel of the MR volume of signal intensity versus time, based on a realistic two-compartment Brix model. Three parameters for this model were fitted: rate of Gd exiting the compartment, representing the extracellular space of a lesion; rate of Gd exiting a blood compartment; and a parameter that characterizes the strength of signal intensities. Curve fitting used for PET/CT and MR series was accomplished by application of the Levenburg-Marquardt nonlinear regression

  8. Wall Painting Investigation by Means of Non-invasive Terahertz Time-Domain Imaging (THz-TDI): Inspection of Subsurface Structures Buried in Historical Plasters

    NASA Astrophysics Data System (ADS)

    Dandolo, Corinna Ludovica Koch; Jepsen, Peter Uhd

    2016-02-01

    Characterization of subsurface features of wall paintings is important in conservation and technical art history as well as in building archaeology and architecture fields. In this study, an area of the apsidal wall painting of Nebbelunde Church (Rødby, Denmark) has been investigated by means of terahertz time-domain imaging (THz-TDI). Subsurface structures have been detected at different depths inside the lime-based plaster of the wall painting until approximately 1 cm from the surface. The surface morphology of the buried structures has been 3D imaged in detail, providing a substantial contribution in their characterization.

  9. Non-invasive diagnostic methods in dentistry

    NASA Astrophysics Data System (ADS)

    Todea, Carmen

    2016-03-01

    The paper, will present the most important non-invasive methods for diagnostic, in different fields of dentistry. Moreover, the laser-based methods will be emphasis. In orthodontics, 3D laser scanners are increasingly being used to establish database for normative population and cross-sectional growth changes but also to asses clinical outcomes in orthognatic surgical and non-surgical treatments. In prevention the main methods for diagnostic of demineralization and caries detection in early stages are represented by laser fluorescence - Quantitative Light Florescence (QLF); DiagnoDent-system-655nm; FOTI-Fiberoptic transillumination; DIFOTI-Digital Imaging Fiberoptic transillumination; and Optical Coherence Tomography (OCT). In odontology, Laser Doppler Flowmetry (LDF) is a noninvasive real time method used for determining the tooth vitality by monitoring the pulp microcirculation in traumatized teeth, fractured teeth, and teeth undergoing different conservative treatments. In periodontology, recently study shows the ability of LDF to evaluate the health of gingival tissue in periodontal tissue diseases but also after different periodontal treatments.

  10. A method to rapidly and accurately compare relative efficacies of non-invasive imaging reporter genes in a mouse model, and its application to luciferase reporters

    PubMed Central

    Gil, Jose S.; Machado, Hidevaldo B.; Herschman, Harvey R.

    2013-01-01

    Purpose Our goal is to develop a simple, quantitative, robust method to compare the efficacy of imaging reporter genes in culture and in vivo. We describe an adenoviral vector-liver transduction procedure, and compare the luciferase reporter efficacies. Procedures Alternative reporter genes are expressed in a common adenoviral vector. Vector amounts used in vivo are based on cell culture titrations, ensuring the same transduction efficacy is used for each vector. After imaging, in vivo and in vitro values are normalized to hepatic vector transduction using quantitative real-time PCR. Results We assayed standard firefly luciferase (FLuc), enhanced firefly luciferase (EFLuc), luciferase 2 (Luc2), humanized Renilla luciferase (hRLuc), Renilla luciferase 8.6-535 (RLuc8.6), and a membrane-bound Gaussia luciferase variant (extGLuc) in cell culture and in vivo. We observed a greater that 100-fold increase in bioluminescent signal for both EFLuc and Luc2 when compared to FLuc, and a greater than 106-fold increase for RLuc8.6 when compared to hRLuc. ExtGLuc was not detectable in liver. Conclusions Our findings contrast, in some cases, with conclusions drawn in prior comparisons of these reporter genes, and demonstrate the need for a standardized method to evaluate alternative reporter genes in vivo. Our procedure can be adapted for reporter genes that utilize alternative imaging modalities (fluorescence, bioluminescence, MRI, SPECT, PET). PMID:21850545

  11. PSMA-Targeted Nano-Conjugates as Dual-Modality (MRI/PET) Imaging Probes for the Non-Invasive Detection of Prostate Cancer

    DTIC Science & Technology

    2009-10-01

    include, bare AuNPs, polymer-coated AuNPs, gadolinium -coated AuNPs and polymer-coated Bi2S3. Molecular CT imaging of cancer using targeted AuNPs in cell...magnetically labeled cells with either gadolinium or iron oxide nanoparticle based agents.1–7 With the much larger ∗Author to whom correspondence...T2) than traditional gadolinium - based contrast agents (T1). However iron oxide based T2 agents also exhibit the inherent weakness of MRI contrast

  12. Non-invasive sensing for food reassurance.

    PubMed

    Xiaobo, Zou; Xiaowei, Huang; Povey, Malcolm

    2016-03-07

    Consumers and governments are increasingly interested in the safety, authenticity and quality of food commodities. This has driven attention towards non-invasive sensing techniques used for rapid analyzing these commodities. This paper provides an overview of the state of the art in, and available alternatives for, food assurance based on non-invasive sensing techniques. The main food quality traits of interest using non-invasive sensing techniques are sensory characteristics, chemical composition, physicochemical properties, health-protecting properties, nutritional characteristics and safety. A wide range of non-invasive sensing techniques, from optical, acoustical, electrical, to nuclear magnetic, X-ray, biosensor, microwave and terahertz, are organized according to physical principle. Some of these techniques are now in a period of transition between experimental and applied utilization and several sensors and instruments are reviewed. With continued innovation and attention to key challenges, such non-invasive sensors and biosensors are expected to open up new exciting avenues in the field of portable and wearable wireless sensing devices and connecting with mobile networks, thus finding considerable use in a wide range of food assurance applications. The need for an appropriate regulatory framework is emphasized which acts to exclude unwanted components in foods and includes needed components, with sensors as part of a reassurance framework supporting regulation and food chain management. The integration of these sensor modalities into a single technological and commercial platform offers an opportunity for a paradigm shift in food reassurance.

  13. A Novel Ideal Radionuclide Imaging System for Non-invasively Cell Monitoring built on Baculovirus Backbone by Introducing Sleeping Beauty Transposon.

    PubMed

    Lv, Jing; Pan, Yu; Ju, Huijun; Zhou, Jinxin; Cheng, Dengfeng; Shi, Hongcheng; Zhang, Yifan

    2017-03-06

    Sleeping Beauty (SB) transposon is an attractive tool in stable transgene integration both in vitro and in vivo; and we introduced SB transposon into recombinant sodium-iodide symporter baculovirus system (Bac-NIS system) to facilitate long-term expression of recombinant sodium-iodide symporter. In our study, two hybrid baculovirus systems (Bac-eGFP-SB-NeoR and Bac-NIS-SB-NeoR) were successfully constructed and used to infect U87 glioma cells. After G418 selection screening, the Bac-eGFP-SB-NeoR-U87 cells remained eGFP positive, at the 18(th) and 196(th) day post transfection (96.03 ± 0.21% and 97.43 ± 0.81%), while eGFP positive population declined significantly at 18 days in cells transfected with unmodified baculovirus construct. NIS gene expression by Bac-NIS-SB-NeoR-U87 cells was also maintained for 28 weeks as determined by radioiodine uptake assay, reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot (WB) assay. When transplanted in mice, Bac-NIS-SB-NeoR-U87 cells also expressed NIS gene stably as monitored by SPECT imaging for 43 days until the tumor-bearing mice were sacrificed. Herein, we showed that incorporation of SB in Bac-NIS system (hybrid Bac-NIS-SB-NeoR) can achieve a long-term transgene expression and can improve radionuclide imaging in cell tracking and monitoring in vivo.

  14. Design of Experiments to Study the Impact of Process Parameters on Droplet Size and Development of Non-Invasive Imaging Techniques in Tablet Coating

    PubMed Central

    Dennison, Thomas J.; Smith, Julian; Hofmann, Michael P.; Bland, Charlotte E.; Badhan, Raj K.; Al-Khattawi, Ali; Mohammed, Afzal R.

    2016-01-01

    Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats. PMID:27548263

  15. A Novel Ideal Radionuclide Imaging System for Non-invasively Cell Monitoring built on Baculovirus Backbone by Introducing Sleeping Beauty Transposon

    PubMed Central

    Lv, Jing; Pan, Yu; Ju, Huijun; Zhou, Jinxin; Cheng, Dengfeng; Shi, Hongcheng; Zhang, Yifan

    2017-01-01

    Sleeping Beauty (SB) transposon is an attractive tool in stable transgene integration both in vitro and in vivo; and we introduced SB transposon into recombinant sodium-iodide symporter baculovirus system (Bac-NIS system) to facilitate long-term expression of recombinant sodium-iodide symporter. In our study, two hybrid baculovirus systems (Bac-eGFP-SB-NeoR and Bac-NIS-SB-NeoR) were successfully constructed and used to infect U87 glioma cells. After G418 selection screening, the Bac-eGFP-SB-NeoR-U87 cells remained eGFP positive, at the 18th and 196th day post transfection (96.03 ± 0.21% and 97.43 ± 0.81%), while eGFP positive population declined significantly at 18 days in cells transfected with unmodified baculovirus construct. NIS gene expression by Bac-NIS-SB-NeoR-U87 cells was also maintained for 28 weeks as determined by radioiodine uptake assay, reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot (WB) assay. When transplanted in mice, Bac-NIS-SB-NeoR-U87 cells also expressed NIS gene stably as monitored by SPECT imaging for 43 days until the tumor-bearing mice were sacrificed. Herein, we showed that incorporation of SB in Bac-NIS system (hybrid Bac-NIS-SB-NeoR) can achieve a long-term transgene expression and can improve radionuclide imaging in cell tracking and monitoring in vivo. PMID:28262785

  16. Probing the in vivo changes in oxygen saturation with photoacoustic imaging as a non-invasive means of assessing treatment progression

    NASA Astrophysics Data System (ADS)

    Hysi, Eno; May, Jonathan P.; Wirtzfeld, Lauren; Undzys, Elijus; Li, Shyh-Dar; Kolios, Michael C.

    2015-03-01

    In vivo photoacoustic estimations of tumor oxygenation were used to assess the therapeutic efficacy of a thermosensitive liposome treatment in a pre-clinical mouse model. The treated group (n = 12) was administered doxorubicin-loaded, heat sensitive liposomes and exposed to mild hyperthermia (43°C) in order to deliver doxorubicin locally within the tumor micro-vessels. Control groups received systemic doxorubicin (n = 7) or saline (n = 12). The changes in tumor blood vessels after treatment were probed by analyzing the frequency content of the photoacoustic radiofrequency signals. Tumor oxygenation dropped by 15-20% during the first 30 minutes post-treatment when the tumors were exposed to encapsulated (Heat-Activated cyToxic - HaT-DOX) or free doxorubicin (DOX). The early (30 minutes to 5 hours) decrease in oxygen saturation strongly correlated to the reduction in tumor size assessed by caliper measurements. Control animals did not exhibit significant changes in tumor oxygenation at the early time points. The oxygenation at 7 days increased significantly for all groups. Measurements of the spectral slope from the normalized power spectra of the photoacoustic signals could also be used to differentiate between responder and non-responder mice. The results of this study suggest that photoacoustic imaging of tumors undergoing vascular-targeted cancer therapy can be used to assess treatment response early (hours) post-treatment through a combined analysis of oxygen saturation and photoacoustic radiofrequency spectroscopy.

  17. Imaging of activated complement using ultrasmall superparamagnetic iron oxide particles (USPIO) - conjugated vectors: an in vivo in utero non-invasive method to predict placental insufficiency and abnormal fetal brain development

    PubMed Central

    Girardi, G; Fraser, J; Lennen, R; Vontell, R; Jansen, M; Hutchison, G

    2015-01-01

    In the current study, we have developed a magnetic resonance imaging-based method for non-invasive detection of complement activation in placenta and foetal brain in vivo in utero. Using this method, we found that anti-complement C3-targeted ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles bind within the inflamed placenta and foetal brain cortical tissue, causing a shortening of the T2* relaxation time. We used two mouse models of pregnancy complications: a mouse model of obstetrics antiphospholipid syndrome (APS) and a mouse model of preterm birth (PTB). We found that detection of C3 deposition in the placenta in the APS model was associated with placental insufficiency characterised by increased oxidative stress, decreased vascular endothelial growth factor and placental growth factor levels and intrauterine growth restriction. We also found that foetal brain C3 deposition was associated with cortical axonal cytoarchitecture disruption and increased neurodegeneration in the mouse model of APS and in the PTB model. In the APS model, foetuses that showed increased C3 in their brains additionally expressed anxiety-related behaviour after birth. Importantly, USPIO did not affect pregnancy outcomes and liver function in the mother and the offspring, suggesting that this method may be useful for detecting complement activation in vivo in utero and predicting placental insufficiency and abnormal foetal neurodevelopment that leads to neuropsychiatric disorders. PMID:25245499

  18. Non-invasive Imaging of Sendai Virus Infection in Pharmacologically Immunocompromised Mice: NK and T Cells, but not Neutrophils, Promote Viral Clearance after Therapy with Cyclophosphamide and Dexamethasone.

    PubMed

    Mostafa, Heba H; Vogel, Peter; Srinivasan, Ashok; Russell, Charles J

    2016-09-01

    In immunocompromised patients, parainfluenza virus (PIV) infections have an increased potential to spread to the lower respiratory tract (LRT), resulting in increased morbidity and mortality. Understanding the immunologic defects that facilitate viral spread to the LRT will help in developing better management protocols. In this study, we immunosuppressed mice with dexamethasone and/or cyclophosphamide then monitored the spread of viral infection into the LRT by using a noninvasive bioluminescence imaging system and a reporter Sendai virus (murine PIV type 1). Our results show that immunosuppression led to delayed viral clearance and increased viral loads in the lungs. After cessation of cyclophosphamide treatment, viral clearance occurred before the generation of Sendai-specific antibody responses and coincided with rebounds in neutrophils, T lymphocytes, and natural killer (NK) cells. Neutrophil suppression using anti-Ly6G antibody had no effect on infection clearance, NK-cell suppression using anti-NK antibody delayed clearance, and T-cell suppression using anti-CD3 antibody resulted in no clearance (chronic infection). Therapeutic use of hematopoietic growth factors G-CSF and GM-CSF had no effect on clearance of infection. In contrast, treatment with Sendai virus-specific polysera or a monoclonal antibody limited viral spread into the lungs and accelerated clearance. Overall, noninvasive bioluminescence was shown to be a useful tool to study respiratory viral progression, revealing roles for NK and T cells, but not neutrophils, in Sendai virus clearance after treatment with dexamethasone and cyclophosphamide. Virus-specific antibodies appear to have therapeutic potential.

  19. Non-invasive Imaging of Sendai Virus Infection in Pharmacologically Immunocompromised Mice: NK and T Cells, but not Neutrophils, Promote Viral Clearance after Therapy with Cyclophosphamide and Dexamethasone

    PubMed Central

    Mostafa, Heba H.; Vogel, Peter; Srinivasan, Ashok; Russell, Charles J.

    2016-01-01

    In immunocompromised patients, parainfluenza virus (PIV) infections have an increased potential to spread to the lower respiratory tract (LRT), resulting in increased morbidity and mortality. Understanding the immunologic defects that facilitate viral spread to the LRT will help in developing better management protocols. In this study, we immunosuppressed mice with dexamethasone and/or cyclophosphamide then monitored the spread of viral infection into the LRT by using a noninvasive bioluminescence imaging system and a reporter Sendai virus (murine PIV type 1). Our results show that immunosuppression led to delayed viral clearance and increased viral loads in the lungs. After cessation of cyclophosphamide treatment, viral clearance occurred before the generation of Sendai-specific antibody responses and coincided with rebounds in neutrophils, T lymphocytes, and natural killer (NK) cells. Neutrophil suppression using anti-Ly6G antibody had no effect on infection clearance, NK-cell suppression using anti-NK antibody delayed clearance, and T-cell suppression using anti-CD3 antibody resulted in no clearance (chronic infection). Therapeutic use of hematopoietic growth factors G-CSF and GM-CSF had no effect on clearance of infection. In contrast, treatment with Sendai virus—specific polysera or a monoclonal antibody limited viral spread into the lungs and accelerated clearance. Overall, noninvasive bioluminescence was shown to be a useful tool to study respiratory viral progression, revealing roles for NK and T cells, but not neutrophils, in Sendai virus clearance after treatment with dexamethasone and cyclophosphamide. Virus-specific antibodies appear to have therapeutic potential. PMID:27589232

  20. Non-invasive assessments of adipose tissue metabolism in vitro

    PubMed Central

    Abbott, Rosalyn D.; Borowsky, Francis E.; Quinn, Kyle P.; Bernstein, David L.; Georgakoudi, Irene; Kaplan, David L.

    2015-01-01

    Adipose tissue engineering is a diverse area of research where the developed tissues can be used to study normal adipose tissue functions, create disease models in vitro, and replace soft tissue defects in vivo. Increasing attention has been focused on the highly specialized metabolic pathways that regulate energy storage and release in adipose tissues which affect local and systemic outcomes. Non-invasive, dynamic measurement systems are useful to track these metabolic pathways in the same tissue model over time to evaluate long term cell growth, differentiation, and development within tissue engineering constructs. This approach reduces costs and time in comparison to more traditional destructive methods such as biochemical and immunochemistry assays and proteomics assessments. Towards this goal, this review will focus on important metabolic functions of adipose tissues and strategies to evaluate them with noninvasive in vitro methods. Current non-invasive methods, such as measuring key metabolic markers and endogenous contrast imaging will be explored. PMID:26399988

  1. Hepatic steatosis and fibrosis: Non-invasive assessment

    PubMed Central

    Karanjia, Rustam N; Crossey, Mary M E; Cox, I Jane; Fye, Haddy K S; Njie, Ramou; Goldin, Robert D; Taylor-Robinson, Simon D

    2016-01-01

    Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and non-invasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy. PMID:28018096

  2. Engraftment and bone mass are enhanced by PTHrP 1-34 in ectopically transplanted vertebrae (vossicle model) and can be non-invasively monitored with bioluminescence and fluorescence imaging

    PubMed Central

    Hildreth, Blake Eason; Williams, Michelle C.; Dembek, Katarzyna A.; Hernon, Krista M.; Rosol, Thomas J.; Toribio, Ramiro E.

    2015-01-01

    Evidence exists that parathyroid hormone-related protein (PTHrP) 1-34 may be more anabolic in bone than parathyroid hormone (PTH) 1-34. While optical imaging is growing in popularity, scant information exists on the relationships between traditional bone imaging and histology and bioluminescence (BLI) and fluorescence (FLI) imaging. We aimed to evaluate the effects of PTHrP 1-34 on bone mass and determine if relationships existed between radiographic and histologic findings in bone and BLI and FLI indices. Vertebrae (vossicles) from mice coexpressing luciferase and green fluorescent protein were implanted subcutaneously into allogenic nude mice. Transplant recipients were treated daily with saline or PTHrP 1-34 for 4 weeks. BLI, FLI, radiography, histology, and μCT of the vossicles were performed over time. PTHrP 1-34 increased bioluminescence the most after 2 weeks, fluorescence at all time points, and decreased the time to peak bioluminescence at 4 weeks (P ≤ 0.027), the latter of which suggesting enhanced engraftment. PTHrP 1-34 maximized vertebral body volume at 4 weeks (P < 0.0001). The total amount of bone observed histologically increased in both groups at 2 and 4 weeks (P ≤ 0.002); however, PTHrP 1-34 exceeded time-matched controls (P ≤ 0.044). A positive linear relationship existed between the percentage of trabecular bone and 1) total bioluminescence (r = 0.595; P = 0.019); 2) total fluorescence (r = 0.474; P = 0.074); and 3) max fluorescence (r = 0.587; P = 0.021). In conclusion, PTHrP 1-34 enhances engraftment and bone mass, which can be monitored non-invasively by BLI and FLI. PMID:26271486

  3. Engraftment and bone mass are enhanced by PTHrP 1-34 in ectopically transplanted vertebrae (vossicle model) and can be non-invasively monitored with bioluminescence and fluorescence imaging.

    PubMed

    Hildreth, Blake Eason; Williams, Michelle M; Dembek, Katarzyna A; Hernon, Krista M; Rosol, Thomas J; Toribio, Ramiro E

    2015-12-01

    Evidence exists that parathyroid hormone-related protein (PTHrP) 1-34 may be more anabolic in bone than parathyroid hormone 1-34. While optical imaging is growing in popularity, scant information exists on the relationships between traditional bone imaging and histology and bioluminescence (BLI) and fluorescence (FLI) imaging. We aimed to evaluate the effects of PTHrP 1-34 on bone mass and determine if relationships existed between radiographic and histologic findings in bone and BLI and FLI indices. Vertebrae (vossicles) from mice coexpressing luciferase and green fluorescent protein were implanted subcutaneously into allogenic nude mice. Transplant recipients were treated daily with saline or PTHrP 1-34 for 4 weeks. BLI, FLI, radiography, histology, and µCT of the vossicles were performed over time. PTHrP 1-34 increased bioluminescence the most after 2 weeks, fluorescence at all time points, and decreased the time to peak bioluminescence at 4 weeks (P ≤ 0.027), the latter of which suggesting enhanced engraftment. PTHrP 1-34 maximized vertebral body volume at 4 weeks (P < 0.0001). The total amount of bone observed histologically increased in both groups at 2 and 4 weeks (P ≤ 0.002); however, PTHrP 1-34 exceeded time-matched controls (P ≤ 0.044). A positive linear relationship existed between the percentage of trabecular bone and (1) total bioluminescence (r = 0.595; P = 0.019); (2) total fluorescence (r = 0.474; P = 0.074); and (3) max fluorescence (r = 0.587; P = 0.021). In conclusion, PTHrP 1-34 enhances engraftment and bone mass, which can be monitored non-invasively by BLI and FLI.

  4. Non-invasive methods for the determination of body and carcass composition in livestock: dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging and ultrasound: invited review.

    PubMed

    Scholz, A M; Bünger, L; Kongsro, J; Baulain, U; Mitchell, A D

    2015-07-01

    The ability to accurately measure body or carcass composition is important for performance testing, grading and finally selection or payment of meat-producing animals. Advances especially in non-invasive techniques are mainly based on the development of electronic and computer-driven methods in order to provide objective phenotypic data. The preference for a specific technique depends on the target animal species or carcass, combined with technical and practical aspects such as accuracy, reliability, cost, portability, speed, ease of use, safety and for in vivo measurements the need for fixation or sedation. The techniques rely on specific device-driven signals, which interact with tissues in the body or carcass at the atomic or molecular level, resulting in secondary or attenuated signals detected by the instruments and analyzed quantitatively. The electromagnetic signal produced by the instrument may originate from mechanical energy such as sound waves (ultrasound - US), 'photon' radiation (X-ray-computed tomography - CT, dual-energy X-ray absorptiometry - DXA) or radio frequency waves (magnetic resonance imaging - MRI). The signals detected by the corresponding instruments are processed to measure, for example, tissue depths, areas, volumes or distributions of fat, muscle (water, protein) and partly bone or bone mineral. Among the above techniques, CT is the most accurate one followed by MRI and DXA, whereas US can be used for all sizes of farm animal species even under field conditions. CT, MRI and US can provide volume data, whereas only DXA delivers immediate whole-body composition results without (2D) image manipulation. A combination of simple US and more expensive CT, MRI or DXA might be applied for farm animal selection programs in a stepwise approach.

  5. Non-invasive diagnosis of advanced fibrosis and cirrhosis.

    PubMed

    Sharma, Suraj; Khalili, Korosh; Nguyen, Geoffrey Christopher

    2014-12-07

    Liver cirrhosis is a common and growing public health problem globally. The diagnosis of cirrhosis portends an increased risk of morbidity and mortality. Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis. However, despite its universal use, liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks. In order to overcome the limitations of liver biopsy, a number of non-invasive techniques have been investigated for the assessment of cirrhosis. This review will focus on currently available non-invasive markers of cirrhosis. The evidence behind the use of these markers will be highlighted, along with an assessment of diagnostic accuracy and performance characteristics of each test. Non-invasive markers of cirrhosis can be radiologic or serum-based. Radiologic techniques based on ultrasound, magnetic resonance imaging and elastography have been used to assess liver fibrosis. Serum-based biomarkers of cirrhosis have also been developed. These are broadly classified into indirect and direct markers. Indirect biomarkers reflect liver function, which may decline with the onset of cirrhosis. Direct biomarkers, reflect extracellular matrix turnover, and include molecules involved in hepatic fibrogenesis. On the whole, radiologic and serum markers of fibrosis correlate well with biopsy scores, especially when excluding cirrhosis or excluding fibrosis. This feature is certainly clinically useful, and avoids liver biopsy in many cases.

  6. Infrared thermography: A non-invasive window into thermal physiology.

    PubMed

    Tattersall, Glenn J

    2016-12-01

    Infrared thermography is a non-invasive technique that measures mid to long-wave infrared radiation emanating from all objects and converts this to temperature. As an imaging technique, the value of modern infrared thermography is its ability to produce a digitized image or high speed video rendering a thermal map of the scene in false colour. Since temperature is an important environmental parameter influencing animal physiology and metabolic heat production an energetically expensive process, measuring temperature and energy exchange in animals is critical to understanding physiology, especially under field conditions. As a non-contact approach, infrared thermography provides a non-invasive complement to physiological data gathering. One caveat, however, is that only surface temperatures are measured, which guides much research to those thermal events occurring at the skin and insulating regions of the body. As an imaging technique, infrared thermal imaging is also subject to certain uncertainties that require physical modelling, which is typically done via built-in software approaches. Infrared thermal imaging has enabled different insights into the comparative physiology of phenomena ranging from thermogenesis, peripheral blood flow adjustments, evaporative cooling, and to respiratory physiology. In this review, I provide background and guidelines for the use of thermal imaging, primarily aimed at field physiologists and biologists interested in thermal biology. I also discuss some of the better known approaches and discoveries revealed from using thermal imaging with the objective of encouraging more quantitative assessment.

  7. A theoretical and experimental evaluation of the microangiographic fluoroscope: A high-resolution region-of-interest x-ray imager

    SciTech Connect

    Jain, Amit; Bednarek, D. R.; Ionita, Ciprian; Rudin, S.

    2011-07-15

    Purpose: The increasing need for better image quality and high spatial resolution for successful endovascular image-guided interventions (EIGIs) and the inherent limitations of the state-of-the-art detectors provide motivation to develop a detector system tailored to the specific, demanding requirements of neurointerventional applications.Method: A microangiographic fluoroscope (MAF) was developed to serve as a high-resolution, region-of-interest (ROI) x-ray imaging detector in conjunction with large lower-resolution full field-of-view (FOV) state-of-the-art x-ray detectors. The newly developed MAF is an indirect x-ray imaging detector capable of providing real-time images (30 frames per second) with high-resolution, high sensitivity, no lag and low instrumentation noise. It consists of a CCD camera coupled to a Gen 2 dual-stage microchannel plate light image intensifier (LII) through a fiber-optic taper. A 300 {mu}m thick CsI(Tl) phosphor serving as the front end is coupled to the LII. The LII is the key component of the MAF and the large variable gain provided by it enables the MAF to operate as a quantum-noise-limited detector for both fluoroscopy and angiography. Results: The linear cascade model was used to predict the theoretical performance of the MAF, and the theoretical prediction showed close agreement with experimental findings. Linear system metrics such as MTF and DQE were used to gauge the detector performance up to 10 cycles/mm. The measured zero frequency DQE(0) was 0.55 for an RQA5 spectrum. A total of 21 stages were identified for the whole imaging chain and each stage was characterized individually. Conclusions: The linear cascade model analysis provides insight into the imaging chain and may be useful for further development of the MAF detector. The preclinical testing of the prototype detector in animal procedures is showing encouraging results and points to the potential for significant impact on EIGIs when used in conjunction with a state

  8. A new tool for benchmarking cardiovascular fluoroscopes.

    PubMed

    Balter, S; Heupler, F A; Lin, P J; Wondrow, M H

    2001-01-01

    This article reports the status of a new cardiovascular fluoroscopy benchmarking phantom. A joint working group of the Society for Cardiac Angiography and Interventions (SCA&I) and the National Electrical Manufacturers Association (NEMA) developed the phantom. The device was adopted as NEMA standard XR 21-2000, "Characteristics of and Test Procedures for a Phantom to Benchmark Cardiac Fluoroscopic and Photographic Performance," in August 2000. The test ensemble includes imaging field geometry, spatial resolution, low-contrast iodine detectability, working thickness range, visibility of moving targets, and phantom entrance dose. The phantom tests systems under conditions simulating normal clinical use for fluoroscopically guided invasive and interventional procedures. Test procedures rely on trained human observers.

  9. Ultrasonic non invasive techniques for microbiological instrumentation

    NASA Astrophysics Data System (ADS)

    Elvira, L.; Sierra, C.; Galán, B.; Resa, P.

    2010-01-01

    Non invasive techniques based on ultrasounds have advantageous features to study, characterize and monitor microbiological and enzymatic reactions. These processes may change the sound speed, viscosity or particle distribution size of the medium where they take place, which makes possible their analysis using ultrasonic techniques. In this work, two different systems for the analysis of microbiological liquid media based on ultrasounds are presented. In first place, an industrial application based on an ultrasonic monitoring technique for microbiological growth detection in milk is shown. Such a system may improve the quality control strategies in food production factories, being able to decrease the time required to detect possible contaminations in packed products. Secondly, a study about the growing of the Escherichia coli DH5 α in different conditions is presented. It is shown that the use of ultrasonic non invasive characterization techniques in combination with other conventional measurements like optical density provides complementary information about the metabolism of these bacteria.

  10. [Non-invasive assessment of liver fibrosis].

    PubMed

    Cohen-Ezra, Oranit; Ben-Ari, Ziv

    2015-03-01

    Chronic liver diseases represent a major public health problem, accounting for significant morbidity and mortality worldwide. Prognosis and management of chronic liver diseases depend on the amount of liver fibrosis. Liver biopsy has long remained the gold standard for assessment of liver fibrosis. Liver biopsy is an invasive procedure with associated morbidity, it is rarely the cause for mortality, and has a few limitations. During the past two decades, in an attempt to overcome the limitations of liver biopsy, non-invasive methods for the evaluation of liver fibrosis have been developed, mainly in the field of viral hepatitis. This review will focus on different methods available for non-invasive evaluation of liver fibrosis including a biological approach which quantifies serum levels of biomarkers of fibrosis and physical techniques which measure liver stiffness by transient elastography, ultrasound or magnetic resonance based elastography, their accuracy, advantages and disadvantages.

  11. Generation of fluoroscopic 3D images with a respiratory motion model based on an external surrogate signal.

    PubMed

    Hurwitz, Martina; Williams, Christopher L; Mishra, Pankaj; Rottmann, Joerg; Dhou, Salam; Wagar, Matthew; Mannarino, Edward G; Mak, Raymond H; Lewis, John H

    2015-01-21

    Respiratory motion during radiotherapy can cause uncertainties in definition of the target volume and in estimation of the dose delivered to the target and healthy tissue. In this paper, we generate volumetric images of the internal patient anatomy during treatment using only the motion of a surrogate signal. Pre-treatment four-dimensional CT imaging is used to create a patient-specific model correlating internal respiratory motion with the trajectory of an external surrogate placed on the chest. The performance of this model is assessed with digital and physical phantoms reproducing measured irregular patient breathing patterns. Ten patient breathing patterns are incorporated in a digital phantom. For each patient breathing pattern, the model is used to generate images over the course of thirty seconds. The tumor position predicted by the model is compared to ground truth information from the digital phantom. Over the ten patient breathing patterns, the average absolute error in the tumor centroid position predicted by the motion model is 1.4 mm. The corresponding error for one patient breathing pattern implemented in an anthropomorphic physical phantom was 0.6 mm. The global voxel intensity error was used to compare the full image to the ground truth and demonstrates good agreement between predicted and true images. The model also generates accurate predictions for breathing patterns with irregular phases or amplitudes.

  12. Generation of fluoroscopic 3D images with a respiratory motion model based on an external surrogate signal

    NASA Astrophysics Data System (ADS)

    Hurwitz, Martina; Williams, Christopher L.; Mishra, Pankaj; Rottmann, Joerg; Dhou, Salam; Wagar, Matthew; Mannarino, Edward G.; Mak, Raymond H.; Lewis, John H.

    2015-01-01

    Respiratory motion during radiotherapy can cause uncertainties in definition of the target volume and in estimation of the dose delivered to the target and healthy tissue. In this paper, we generate volumetric images of the internal patient anatomy during treatment using only the motion of a surrogate signal. Pre-treatment four-dimensional CT imaging is used to create a patient-specific model correlating internal respiratory motion with the trajectory of an external surrogate placed on the chest. The performance of this model is assessed with digital and physical phantoms reproducing measured irregular patient breathing patterns. Ten patient breathing patterns are incorporated in a digital phantom. For each patient breathing pattern, the model is used to generate images over the course of thirty seconds. The tumor position predicted by the model is compared to ground truth information from the digital phantom. Over the ten patient breathing patterns, the average absolute error in the tumor centroid position predicted by the motion model is 1.4 mm. The corresponding error for one patient breathing pattern implemented in an anthropomorphic physical phantom was 0.6 mm. The global voxel intensity error was used to compare the full image to the ground truth and demonstrates good agreement between predicted and true images. The model also generates accurate predictions for breathing patterns with irregular phases or amplitudes.

  13. Ultrahigh-speed non-invasive widefield angiography

    NASA Astrophysics Data System (ADS)

    Blatter, Cedric; Klein, Thomas; Grajciar, Branislav; Schmoll, Tilman; Wieser, Wolfgang; Andre, Raphael; Huber, Robert; Leitgeb, Rainer A.

    2012-07-01

    Retinal and choroidal vascular imaging is an important diagnostic benefit for ocular diseases such as age-related macular degeneration. The current gold standard for vessel visualization is fluorescence angiography. We present a potential non-invasive alternative to image blood vessels based on functional Fourier domain optical coherence tomography (OCT). For OCT to compete with the field of view and resolution of angiography while maintaining motion artifacts to a minimum, ultrahigh-speed imaging has to be introduced. We employ Fourier domain mode locking swept source technology that offers high quality imaging at an A-scan rate of up to 1.68 MHz. We present retinal angiogram over ˜48 deg acquired in a few seconds in a single recording without the need of image stitching. OCT at 1060 nm allows for high penetration in the choroid and efficient separate characterization of the retinal and choroidal vascularization.

  14. Graphics processing unit (GPU) implementation of image processing algorithms to improve system performance of the control acquisition, processing, and image display system (CAPIDS) of the micro-angiographic fluoroscope (MAF)

    NASA Astrophysics Data System (ADS)

    Swetadri Vasan, S. N.; Ionita, Ciprian N.; Titus, A. H.; Cartwright, A. N.; Bednarek, D. R.; Rudin, S.

    2012-03-01

    We present the image processing upgrades implemented on a Graphics Processing Unit (GPU) in the Control, Acquisition, Processing, and Image Display System (CAPIDS) for the custom Micro-Angiographic Fluoroscope (MAF) detector. Most of the image processing currently implemented in the CAPIDS system is pixel independent; that is, the operation on each pixel is the same and the operation on one does not depend upon the result from the operation on the other, allowing the entire image to be processed in parallel. GPU hardware was developed for this kind of massive parallel processing implementation. Thus for an algorithm which has a high amount of parallelism, a GPU implementation is much faster than a CPU implementation. The image processing algorithm upgrades implemented on the CAPIDS system include flat field correction, temporal filtering, image subtraction, roadmap mask generation and display window and leveling. A comparison between the previous and the upgraded version of CAPIDS has been presented, to demonstrate how the improvement is achieved. By performing the image processing on a GPU, significant improvements (with respect to timing or frame rate) have been achieved, including stable operation of the system at 30 fps during a fluoroscopy run, a DSA run, a roadmap procedure and automatic image windowing and leveling during each frame.

  15. Graphics Processing Unit (GPU) implementation of image processing algorithms to improve system performance of the Control, Acquisition, Processing, and Image Display System (CAPIDS) of the Micro-Angiographic Fluoroscope (MAF).

    PubMed

    Vasan, S N Swetadri; Ionita, Ciprian N; Titus, A H; Cartwright, A N; Bednarek, D R; Rudin, S

    2012-02-23

    We present the image processing upgrades implemented on a Graphics Processing Unit (GPU) in the Control, Acquisition, Processing, and Image Display System (CAPIDS) for the custom Micro-Angiographic Fluoroscope (MAF) detector. Most of the image processing currently implemented in the CAPIDS system is pixel independent; that is, the operation on each pixel is the same and the operation on one does not depend upon the result from the operation on the other, allowing the entire image to be processed in parallel. GPU hardware was developed for this kind of massive parallel processing implementation. Thus for an algorithm which has a high amount of parallelism, a GPU implementation is much faster than a CPU implementation. The image processing algorithm upgrades implemented on the CAPIDS system include flat field correction, temporal filtering, image subtraction, roadmap mask generation and display window and leveling. A comparison between the previous and the upgraded version of CAPIDS has been presented, to demonstrate how the improvement is achieved. By performing the image processing on a GPU, significant improvements (with respect to timing or frame rate) have been achieved, including stable operation of the system at 30 fps during a fluoroscopy run, a DSA run, a roadmap procedure and automatic image windowing and leveling during each frame.

  16. SU-E-I-37: Low-Dose Real-Time Region-Of-Interest X-Ray Fluoroscopic Imaging with a GPU-Accelerated Spatially Different Bilateral Filtering

    SciTech Connect

    Chung, H; Lee, J; Pua, R; Cho, S; Jung, W

    2014-06-01

    Purpose: The purpose of our study is to reduce imaging radiation dose while maintaining image quality of region of interest (ROI) in X-ray fluoroscopy. A low-dose real-time ROI fluoroscopic imaging technique which includes graphics-processing-unit- (GPU-) accelerated image processing for brightness compensation and noise filtering was developed in this study. Methods: In our ROI fluoroscopic imaging, a copper filter is placed in front of the X-ray tube. The filter contains a round aperture to reduce radiation dose to outside of the aperture. To equalize the brightness difference between inner and outer ROI regions, brightness compensation was performed by use of a simple weighting method that applies selectively to the inner ROI, the outer ROI, and the boundary zone. A bilateral filtering was applied to the images to reduce relatively high noise in the outer ROI images. To speed up the calculation of our technique for real-time application, the GPU-acceleration was applied to the image processing algorithm. We performed a dosimetric measurement using an ion-chamber dosimeter to evaluate the amount of radiation dose reduction. The reduction of calculation time compared to a CPU-only computation was also measured, and the assessment of image quality in terms of image noise and spatial resolution was conducted. Results: More than 80% of dose was reduced by use of the ROI filter. The reduction rate depended on the thickness of the filter and the size of ROI aperture. The image noise outside the ROI was remarkably reduced by the bilateral filtering technique. The computation time for processing each frame image was reduced from 3.43 seconds with single CPU to 9.85 milliseconds with GPU-acceleration. Conclusion: The proposed technique for X-ray fluoroscopy can substantially reduce imaging radiation dose to the patient while maintaining image quality particularly in the ROI region in real-time.

  17. Fluoroscopic studies of the upper gastrointestinal tract: techniques and indications.

    PubMed

    Sánchez-Carpintero de la Vega, M; García Villar, C

    2017-01-25

    Fluoroscopic studies of the gastrointestinal tract are becoming increasing less common due to the introduction of other imaging techniques such as computed tomography and magnetic resonance imaging and to the increased availability of endoscopy. Nevertheless, fluoroscopic studies of the gastrointestinal tract continue to appear in clinical guidelines and some of their indications are still valid. These studies are dynamic, operator-dependent examinations that require training to obtain the maximum diagnostic performance. This review aims to describe the technique and bring the indications for this imaging modality up to date.

  18. A review on the non-invasive evaluation of skeletal muscle oxygenation

    NASA Astrophysics Data System (ADS)

    Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

    2016-07-01

    The aim of this review is to conduct a feasibility study of non-invasive evaluation in skeletal muscle oxygenation. This non-invasive evaluation could extract many information using a safe non-invasive method regarding to the oxygenation and microcirculation status in human blood muscle. This brief review highlights the progress of the application of NIRS to evaluate skeletal muscle oxygenation in various activity of human nature from the historical point of view to the present advancement. Since the discovery of non-invasive optical method during 1992, there are many non-invasive techniques uses optical properties on human subject such as near infrared spectroscopy NIRS, optical topography, functional near infrared spectroscopy fNIRS and imaging fNIRI. Furthermore, in this paper we discuss the light absorption potential (LAP) towards chromophores content inside human muscle. Modified beer lambert law was studied in order to build a better understanding toward LAP between chromophores under tissue multilayers in human muscle. This paper will describe the NIRS principle and the basis for its proposed used in skeletal muscle oxygenation. This will cover the advantages and limitation of such application. Thus, these non-invasive techniques could open other possibilities to study muscle performance diagnosis.

  19. Non-invasive methods for embryo selection

    PubMed Central

    Sallam, HN; Sallam, NH; Sallam, SH

    2016-01-01

    Abstract With the widespread use of assisted reproduction, a simple and practical method for embryo selection is needed to optimize the chances of pregnancy while diminishing the incidence of multiple pregnancy and its accompanying problems. Many non-invasive methods for embryo selection have been proposed and some are more promising than others. This review summarizes these methods and attempts to evaluate them in the light of the best currently available evidence and to find out whether any of them is ripe for replacing or supplementing the time-honored method of morphological assessment. PMID:27909565

  20. Non-invasive assessment of cardiac output in children.

    PubMed Central

    Richardson, J R; Ferguson, J; Hiscox, J; Rawles, J

    1998-01-01

    BACKGROUND: Stroke distance, the systolic velocity integral of aortic blood flow, is a linear analogue of stroke volume; its product with heart rate is minute distance, analogous to cardiac output. OBJECTIVE: To investigate the feasibility of assessing cardiac output in children with a simple non-invasive Doppler ultrasound technique, and to determine the normal range of values. METHODS: Peak aortic blood velocity, stroke distance, and minute distance were measured through the suprasternal window in 166 children (mean age 9.6 years, range 2-14) using a portable non-imaging Doppler ultrasound instrument. RESULTS: The technique was well tolerated by all the children participating. Mean peak aortic blood velocity was 138 cm/s and was independent of age. Mean stroke distance was 31.8 cm and showed a small but significant increase with age; mean minute distance was 2490 cm and fell with age, as did heart rate. CONCLUSIONS: Suprasternal Doppler ultrasound measurement of stroke distance is a convenient, well tolerated, non-invasive technique for the assessment of cardiac output in children. The normal range of values during childhood has been established. The technique has great potential for assessing hypovolaemia in children. Images p307-a PMID:9785155

  1. Non-invasive diagnosis of liver fibrosis and cirrhosis.

    PubMed

    Lurie, Yoav; Webb, Muriel; Cytter-Kuint, Ruth; Shteingart, Shimon; Lederkremer, Gerardo Z

    2015-11-07

    The evaluation and follow up of liver fibrosis and cirrhosis have been traditionally performed by liver biopsy. However, during the last 20 years, it has become evident that this "gold-standard" is imperfect; even according to its proponents, it is only "the best" among available methods. Attempts at uncovering non-invasive diagnostic tools have yielded multiple scores, formulae, and imaging modalities. All are better tolerated, safer, more acceptable to the patient, and can be repeated essentially as often as required. Most are much less expensive than liver biopsy. Consequently, their use is growing, and in some countries the number of biopsies performed, at least for routine evaluation of hepatitis B and C, has declined sharply. However, the accuracy and diagnostic value of most, if not all, of these methods remains controversial. In this review for the practicing physician, we analyze established and novel biomarkers and physical techniques. We may be witnessing in recent years the beginning of the end of the first phase for the development of non-invasive markers. Early evidence suggests that they might be at least as good as liver biopsy. Novel experimental markers and imaging techniques could produce a dramatic change in diagnosis in the near future.

  2. In vivo non-invasive multiphoton tomography of human skin

    NASA Astrophysics Data System (ADS)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  3. Implementation of a high-sensitivity Micro-Angiographic Fluoroscope (HS-MAF) for in-vivo endovascular image guided interventions (EIGI) and region-of-interest computed tomography (ROI-CT).

    PubMed

    Ionita, C N; Keleshis, C; Patel, V; Yadava, G; Hoffmann, K R; Bednarek, D R; Jain, A; Rudin, S

    2008-01-01

    New advances in catheter technology and remote actuation for minimally invasive procedures are continuously increasing the demand for better x-ray imaging technology. The new x-ray high-sensitivity Micro-Angiographic Fluoroscope (HS-MAF) detector offers high resolution and real-time image-guided capabilities which are unique when compared with commercially available detectors. This detector consists of a 300 μm CsI input phosphor coupled to a dual stage GEN2 micro-channel plate light image intensifier (LII), followed by minifying fiber-optic taper coupled to a CCD chip. The HS-MAF detector image array is 1024×1024 pixels, with a 12 bit depth capable of imaging at 30 frames per second. The detector has a round field of view with 4 cm diameter and 35 microns pixels. The LII has a large variable gain which allows usage of the detector at very low exposures characteristic of fluoroscopic ranges while maintaining very good image quality. The custom acquisition program allows real-time image display and data storage. We designed a set of in-vivo experimental interventions in which placement of specially designed endovascular stents were evaluated with the new detector and with a standard x-ray image intensifier (XII). Capabilities such fluoroscopy, angiography and ROI-CT reconstruction using rotational angiography data were implemented and verified. The images obtained during interventions under radiographic control with the HS-MAF detector were superior to those with the XII. In general, the device feature markers, the device structures, and the vessel geometry were better identified with the new detector. High-resolution detectors such as HS-MAF can vastly improve the accuracy of localization and tracking of devices such stents or catheters.

  4. Non-invasive primate head restraint using thermoplastic masks

    PubMed Central

    Drucker, Caroline B.; Carlson, Monica L.; Toda, Koji; DeWind, Nicholas K.; Platt, Michael L.

    2015-01-01

    Background The success of many neuroscientific studies depends upon adequate head fixation of awake, behaving animals. Typically, this is achieved by surgically affixing a head-restraint prosthesis to the skull. New Method Here we report the use of thermoplastic masks to non-invasively restrain monkeys’ heads. Mesh thermoplastic sheets become pliable when heated and can then be molded to an individual monkey’s head. After cooling, the custom mask retains this shape indefinitely for day-to-day use. Results We successfully trained rhesus macaques (Macaca mulatta) to perform cognitive tasks while wearing thermoplastic masks. Using these masks, we achieved a level of head stability sufficient for high-resolution eye-tracking and intracranial electrophysiology. Comparison with Existing Method Compared with traditional head-posts, we find that thermoplastic masks perform at least as well during infrared eye-tracking and single-neuron recordings, allow for clearer magnetic resonance image acquisition, enable freer placement of a transcranial magnetic stimulation coil, and impose lower financial and time costs on the lab. Conclusions We conclude that thermoplastic masks are a viable non-invasive form of primate head restraint that enable a wide range of neuroscientific experiments. PMID:26112334

  5. Non-invasive neuroimaging using near-infrared light

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Boas, David A.; Sutton, Jeffrey P.

    2002-01-01

    This article reviews diffuse optical brain imaging, a technique that employs near-infrared light to non-invasively probe the brain for changes in parameters relating to brain function. We describe the general methodology, including types of measurements and instrumentation (including the tradeoffs inherent in the various instrument components), and the basic theory required to interpret the recorded data. A brief review of diffuse optical applications is included, with an emphasis on research that has been done with psychiatric populations. Finally, we discuss some practical issues and limitations that are relevant when conducting diffuse optical experiments. We find that, while diffuse optics can provide substantial advantages to the psychiatric researcher relative to the alternative brain imaging methods, the method remains substantially underutilized in this field.

  6. Functionality and operation of fluoroscopic automatic brightness control/automatic dose rate control logic in modern cardiovascular and interventional angiography systems: A Report of Task Group 125 Radiography/Fluoroscopy Subcommittee, Imaging Physics Committee, Science Council

    SciTech Connect

    Rauch, Phillip; Lin, Pei-Jan Paul; Balter, Stephen; Fukuda, Atsushi; Goode, Allen; Hartwell, Gary; LaFrance, Terry; Nickoloff, Edward; Shepard, Jeff; Strauss, Keith

    2012-05-15

    Task Group 125 (TG 125) was charged with investigating the functionality of fluoroscopic automatic dose rate and image quality control logic in modern angiographic systems, paying specific attention to the spectral shaping filters and variations in the selected radiologic imaging parameters. The task group was also charged with describing the operational aspects of the imaging equipment for the purpose of assisting the clinical medical physicist with clinical set-up and performance evaluation. Although there are clear distinctions between the fluoroscopic operation of an angiographic system and its acquisition modes (digital cine, digital angiography, digital subtraction angiography, etc.), the scope of this work was limited to the fluoroscopic operation of the systems studied. The use of spectral shaping filters in cardiovascular and interventional angiography equipment has been shown to reduce patient dose. If the imaging control algorithm were programmed to work in conjunction with the selected spectral filter, and if the generator parameters were optimized for the selected filter, then image quality could also be improved. Although assessment of image quality was not included as part of this report, it was recognized that for fluoroscopic imaging the parameters that influence radiation output, differential absorption, and patient dose are also the same parameters that influence image quality. Therefore, this report will utilize the terminology ''automatic dose rate and image quality'' (ADRIQ) when describing the control logic in modern interventional angiographic systems and, where relevant, will describe the influence of controlled parameters on the subsequent image quality. A total of 22 angiography units were investigated by the task group and of these one each was chosen as representative of the equipment manufactured by GE Healthcare, Philips Medical Systems, Shimadzu Medical USA, and Siemens Medical Systems. All equipment, for which measurement data were

  7. Functionality and operation of fluoroscopic automatic brightness control/automatic dose rate control logic in modern cardiovascular and interventional angiography systems: a report of Task Group 125 Radiography/Fluoroscopy Subcommittee, Imaging Physics Committee, Science Council.

    PubMed

    Rauch, Phillip; Lin, Pei-Jan Paul; Balter, Stephen; Fukuda, Atsushi; Goode, Allen; Hartwell, Gary; LaFrance, Terry; Nickoloff, Edward; Shepard, Jeff; Strauss, Keith

    2012-05-01

    Task Group 125 (TG 125) was charged with investigating the functionality of fluoroscopic automatic dose rate and image quality control logic in modern angiographic systems, paying specific attention to the spectral shaping filters and variations in the selected radiologic imaging parameters. The task group was also charged with describing the operational aspects of the imaging equipment for the purpose of assisting the clinical medical physicist with clinical set-up and performance evaluation. Although there are clear distinctions between the fluoroscopic operation of an angiographic system and its acquisition modes (digital cine, digital angiography, digital subtraction angiography, etc.), the scope of this work was limited to the fluoroscopic operation of the systems studied. The use of spectral shaping filters in cardiovascular and interventional angiography equipment has been shown to reduce patient dose. If the imaging control algorithm were programmed to work in conjunction with the selected spectral filter, and if the generator parameters were optimized for the selected filter, then image quality could also be improved. Although assessment of image quality was not included as part of this report, it was recognized that for fluoroscopic imaging the parameters that influence radiation output, differential absorption, and patient dose are also the same parameters that influence image quality. Therefore, this report will utilize the terminology "automatic dose rate and image quality" (ADRIQ) when describing the control logic in modern interventional angiographic systems and, where relevant, will describe the influence of controlled parameters on the subsequent image quality. A total of 22 angiography units were investigated by the task group and of these one each was chosen as representative of the equipment manufactured by GE Healthcare, Philips Medical Systems, Shimadzu Medical USA, and Siemens Medical Systems. All equipment, for which measurement data were

  8. Implementation of non-invasive brain physiological monitoring concepts.

    PubMed

    Ragauskas, Arminas; Daubaris, Gediminas; Ragaisis, Vytautas; Petkus, Vytautas

    2003-10-01

    The paper presents innovative methods and technology for non-invasive intracranial hemodynamics monitoring based on the measurement of brain parenchyma acoustic properties. The clinical investigation of new technology shows the similarity between the invasively recorded intracranial pressure (ICP) and non-invasively recorded intracranial blood volume (IBV) pulse waves, slow waves and slow trends under intensive care unit (ICU) conditions. Also, the applicability of the non-invasive IBV slow wave monitoring technique for cerebrovascular autoregulation non-invasive long-term monitoring is demonstrated by theoretical and experimental studies.

  9. Long-term non-invasive ventilation in children.

    PubMed

    Amaddeo, Alessandro; Frapin, Annick; Fauroux, Brigitte

    2016-12-01

    Use of long-term non-invasive ventilation is increasing exponentially worldwide in children of all ages. The treatment entails delivery of ventilatory assistance through a non-invasive interface. Indications for use of non-invasive ventilation include conditions that affect normal respiratory balance (eg, those associated with dysfunction of the central drive or respiratory muscles) and disorders characterised by an increase in respiratory load (eg, obstructive airway or lung diseases). The type of non-invasive ventilation used depends on the pathophysiological features of the respiratory failure. For example, non-invasive ventilation will need to either replace central drive if the disorder is characterised by an abnormal central drive or substitute for the respiratory muscles if the condition is associated with respiratory muscle weakness. Non-invasive ventilation might also need to unload the respiratory muscles in case of an increase in respiratory load, as seen in upper airway obstruction and some lung diseases. Technical aspects are also important when choosing non-invasive ventilation-eg, appropriate interface and device. The great heterogeneity of disorders, age ranges of affected children, prognoses, and outcomes of patients needing long-term non-invasive ventilation underline the need for management by skilled multidisciplinary centres with technical competence in paediatric non-invasive ventilation and expertise in sleep studies and therapeutic education.

  10. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    PubMed Central

    Antonacci, Giuseppe; Braakman, Sietse

    2016-01-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p < 0.0001) and the surrounding cytoplasm (p < 0.0001). Moreover, we demonstrate the mechanical response of cells to Latrunculin-A, a drug that reduces cell stiffness by preventing cytoskeletal assembly. Our technique can therefore generate valuable insights into cellular biomechanics and its role in pathophysiology. PMID:27845411

  11. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    NASA Astrophysics Data System (ADS)

    Antonacci, Giuseppe; Braakman, Sietse

    2016-11-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p < 0.0001) and the surrounding cytoplasm (p < 0.0001). Moreover, we demonstrate the mechanical response of cells to Latrunculin-A, a drug that reduces cell stiffness by preventing cytoskeletal assembly. Our technique can therefore generate valuable insights into cellular biomechanics and its role in pathophysiology.

  12. Non invasive sensing technologies for cultural heritage management and fruition

    NASA Astrophysics Data System (ADS)

    Soldovieri, Francesco; Masini, Nicola

    2016-04-01

    The relevance of the information produced by science and technology for the knowledge of the cultural heritage depends on the quality of the feedback and, consequently, on the "cultural" distance between scientists and end-users. In particular, the solution to this problem mainly resides in the capability of end-users' capability to assess and transform the knowledge produced by diagnostics with regard to: information on both cultural objects and sites (decay patterns, vulnerability, presence of buried archaeological remains); decision making (management plan, conservation project, and excavation plan). From our experience in the field of the cultural heritage and namely the conservation, of monuments, there is a significant gap of information between technologists (geophysicists/physicists/engineers) and end-users (conservators/historians/architects). This cultural gap is due to the difficulty to interpret "indirect data" produced by non invasive diagnostics (i.e. radargrams/thermal images/seismic tomography etc..) in order to provide information useful to improve the historical knowledge (e.g. the chronology of the different phases of a building), to characterise the state of conservation (e.g. detection of cracks in the masonry) and to monitor in time cultural heritage artifacts and sites. The possible answer to this difficulty is in the set-up of a knowledge chain regarding the following steps: - Integrated application of novel and robust data processing methods; - Augmented reality as a tool for making easier the interpretation of non invasive - investigations for the analysis of decay pathologies of masonry and architectural surfaces; - The comparison between direct data (carrots, visual inspection) and results from non-invasive tests, including geophysics, aims to improve the interpretation and the rendering of the monuments and even of the archaeological landscapes; - The use of specimens or test beds for the detection of archaeological features and

  13. Integration of kerma-area product and cumulative air kerma determination into a skin dose tracking system for fluoroscopic imaging procedures

    NASA Astrophysics Data System (ADS)

    Vijayan, Sarath; Shankar, Alok; Rudin, Stephen; Bednarek, Daniel R.

    2016-03-01

    The skin dose tracking system (DTS) that we developed provides a color-coded mapping of the cumulative skin dose distribution on a 3D graphic of the patient during fluoroscopic procedures in real time. The DTS has now been modified to also calculate the kerma area product (KAP) and cumulative air kerma (CAK) for fluoroscopic interventions using data obtained in real-time from the digital bus on a Toshiba Infinix system. KAP is the integral of air kerma over the beam area and is typically measured with a large-area transmission ionization chamber incorporated into the collimator assembly. In this software, KAP is automatically determined for each x-ray pulse as the product of the air kerma/ mAs from a calibration file for the given kVp and beam filtration times the mAs per pulse times the length and width of the beam times a field nonuniformity correction factor. Field nonuniformity is primarily the result of the heel effect and the correction factor was determined from the beam profile measured using radio-chromic film. Dividing the KAP by the beam area at the interventional reference point provides the area averaged CAK. The KAP and CAK per x-ray pulse are summed after each pulse to obtain the total procedure values in real-time. The calculated KAP and CAK were compared to the values displayed by the fluoroscopy machine with excellent agreement. The DTS now is able to automatically calculate both KAP and CAK without the need for measurement by an add-on transmission ionization chamber.

  14. Non-invasive assessment of bleeding pulmonary artery aneurysms due to Behçet disease.

    PubMed

    Greene, R M; Saleh, A; Taylor, A K; Callaghan, M; Addis, B J; Nzewi, O C; van Zyl, W V

    1998-01-01

    Because of its ability to depict intravascular, intramural, and extramural pathology, non-invasive imaging is well suited to assessing life-threatening hemoptysis that may complicate Behçet disease. We made exclusive use of CT angiography supplemented by MR to identify pulmonary thromboembolism, mediastinal lymphadenopathy, and bilateral pulmonary artery aneurysms with signs of previous unilateral rupture. Two-dimensional reformatted CT images provided surgeons with a road map of upstream and downstream vascular relationships prior to aneurysm resection. Imaging findings were confirmed by surgery and pathology. Non-invasive imaging proved to be a useful alternative to standard catheter arteriography in the preoperative assessment of hemoptysis in this patient with Behçet disease.

  15. Development and evaluation of a new radiographic and fluoroscopic imager based on electron-multiplying CCDs: The solid state x-ray image intensifier

    NASA Astrophysics Data System (ADS)

    Kuhls-Gilcrist, Andrew Thomas

    A new dual detector system was developed which utilizes a low resolution, large field-of-view x-ray image intensifier (II) and a high resolution, region-of-interest microangiographic (MA) detector on the same c-arm gantry. With this new MA-II system, the larger field-of-view (FOV) II can be operated when the demands of the task are not as high, and a larger imaging area is desired. However, when a higher-resolution image with greater image quality is desired at a targeted region-of-interest (ROI), the MA can be deployed to take on these greater demands. To quantitatively and qualitatively assess the imaging performance of each detector under realistic conditions, angiographic images of simulated vessels and rabbit neurovasculature were acquired with both detectors under nearly identical conditions. With the MA detector deployed, vessels as small as 95 mum were visible, whereas the II could not detect vessels smaller than 235 mum. The ROI MA mode was also shown to provide sharper images with higher contrast-to-noise ratios and was four times as likely to successfully detect overlapping vessels as compared to the II. More accurate three-dimensional center lines of vasculature using multi-view reconstruction techniques were also obtained with the MA. The solid state x-ray image intensifier (SSXII) was developed to provide similar high-resolution imaging capabilities as the MA and a built in adjustable gain to provide high-sensitivity imaging capabilities for operation at all exposures used in medical x-ray imaging procedures. The imaging components used in construction of the prototype SSXII were selected based on a theoretical performance evaluation, using a Fourier-based linear-systems model analysis. The performance of the prototype SSXII was then extensively evaluated. Images of various objects and image comparisons with current state-of-the-art detectors qualitatively demonstrated that the SSXII is capable of providing substantial improvements. A quantitative

  16. Modern non-invasive mechanical ventilation turns 25.

    PubMed

    Díaz Lobato, Salvador; Mayoralas Alises, Sagrario

    2013-11-01

    The history of non-invasive mechanical ventilation goes back more than 100 years, but it was not until 1987 when what we could call "modern" non-invasive mechanical ventilation was developed. The description of Delaubier and Rideau of a patient with Duchenne's disease who had been effectively ventilated through a nasal mask marked the start of a new era in the history of non-invasive mechanical ventilation. Over these last 25years, we have witnessed exponential growth in its use, field of activity and technological advances on an exciting fast-paced track. We believe that it is time to review the main milestones that have marked the development of non-invasive mechanical ventilation to date, while paying homage to this therapeutic method that has contributed so much to the advancement of respiratory medicine in the last 25years.

  17. A new microtomographic technique for non-invasive evaluation of the bone structure around implants.

    PubMed

    Sennerby, L; Wennerberg, A; Pasop, F

    2001-02-01

    A new X-ray microtomographic technique for non-invasive assessment of the structure of bone surrounding implants was tested. Three titanium microimplants retrieved directly (n = 2) or 6 months (n = 1) after insertion in 3 patients were used as test samples. Two samples were used dry and one was embedded in plastic resin prior to microtomography. The technique provided high-resolution consecutive cross-sectional X-ray images of the specimens with a slice-to-slice distance of 4.4 to 11.0 microns. The pictures could be imported into an image analysing software with which semiautomatic quantitative measurement of the bone area and three-dimensional images of the specimens could be made. It is suggested that the technique may be used for non-invasive assessment of the bone structure around implants. Further studies are needed to evaluate the accuracy of the technique, for instance by comparing tomographic sections with histologic ones.

  18. Non-invasive photo acoustic approach for human bone diagnosis.

    PubMed

    Thella, Ashok Kumar; Rizkalla, James; Helmy, Ahdy; Suryadevara, Vinay Kumar; Salama, Paul; Rizkalla, Maher

    2016-12-01

    The existing modalities of bone diagnosis including X-ray and ultrasound may cite drawback in some cases related to health issues and penetration depth, while the ultrasound modality may lack image quality. Photo acoustic approach however, provides light energy to the acoustic wave, enabling it to activate and respond according to the propagating media (which is type of bones in this case). At the same time, a differential temperature change may result in the bio heat response, resulting from the heat absorbed across the multiple materials under study. In this work, we have demonstrated the features of using photo acoustic modality in order to non-invasively diagnose the type of human bones based on their electrical, thermal, and acoustic properties that differentiate the output response of each type. COMSOL software was utilized to combine both acoustic equations and bio heat equations, in order to study both the thermal and acoustic responses through which the differential diagnosis can be obtained. In this study, we solved both the acoustic equation and bio heat equations for four types of bones, bone (cancellous), bone (cortical), bone marrow (red), and bone marrow (yellow). 1 MHz acoustic source frequency was chosen and 10(5) W/m(2) power source was used in the simulation. The simulation tested the dynamic response of the wave over a distance of 5 cm from each side for the source. Near 2.4 cm was detected from simulation from each side of the source with a temperature change of within 0.5 K for various types of bones, citing a promising technique for a practical model to detect the type of bones via the differential temperature as well as the acoustic was response via the multiple materials associated with the human bones (skin and blood). The simulation results suggest that the PA technique may be applied to non-invasive diagnosis for the different types of bones, including cancerous bones. A practical model for detecting both the temperature change via

  19. An optical approach for non-invasive blood clot testing

    NASA Astrophysics Data System (ADS)

    Kalchenko, Vyacheslav; Brill, Alexander; Fine, Ilya; Harmelin, Alon

    2007-02-01

    Physiological blood coagulation is an essential biological process. Current tests for plasma coagulation (clotting) need to be performed ex vivo and require fresh blood sampling for every test. A recently published work describes a new, noninvasive, in vivo approach to assess blood coagulation status during mechanical occlusion1. For this purpose, we have tested this approach and applied a controlled laser beam to blood micro-vessels of the mouse ear during mechanical occlusion. Standard setup for intravital transillumination videomicroscopy and laser based imaging techniques were used for monitoring the blood clotting process. Temporal mechanical occlusion of blood vessels in the observed area was applied to ensure blood flow cessation. Subsequently, laser irradiation was used to induce vascular micro-injury. Changes in the vessel wall, as well as in the pattern of blood flow, predispose the area to vascular thrombosis, according to the paradigm of Virchow's triad. In our experiments, two elements of Virchow's triad were used to induce the process of clotting in vivo, and to assess it optically. We identified several parameters that can serve as markers of the blood clotting process in vivo. These include changes in light absorption in the area of illumination, as well as changes in the pattern of the red blood cells' micro-movement in the vessels where blood flow is completely arrested. Thus, our results indicate that blood coagulation status can be characterized by non-invasive, in vivo methodologies.

  20. Non invasive tools for the diagnosis of liver cirrhosis

    PubMed Central

    Soresi, Maurizio; Giannitrapani, Lydia; Cervello, Melchiorre; Licata, Anna; Montalto, Giuseppe

    2014-01-01

    Liver cirrhosis (LC), the end stage of many forms of chronic hepatitis of different etiologies is a diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules surrounded by annular fibrosis. This chronic progressive clinical condition, leads to liver cell failure and portal hypertension, which can favour the onset of hepatocellular carcinoma. Defining the phase of the natural history is crucial for therapeutic choice and prognosis. Liver biopsy is currently considered the best available standard of reference but it has some limits, so alternative tools have been developed to substitute liver biopsy when assessing liver fibrosis. Serum markers offer a cost-effective alternative to liver biopsy being less invasive and theoretically without complications. They can be classified into direct and indirect markers which may be used alone or in combination to produce composite scores. Diagnostic imaging includes a number of instruments and techniques to estimate liver fibrosis and cirrhosis like ultrasound (US), US Doppler, contrast enhanced US and Elastography. US could be used for the diagnosis of advanced LC while is not able to evaluate progression of fibrosis, in this case Elastography is more reliable. This review aims to revise the most recent data from the literature about non invasive methods useful in defining liver fibrosis. PMID:25561782

  1. Application of optical non-invasive methods in skin physiology

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Patzelt, A.; Darvin, M.; Richter, H.; Antoniou, C.; Sterry, W.; Koch, S.

    2008-05-01

    In the present paper the application of optical non-invasive methods in dermatology and cosmetology is discussed. Laser scanning microscopy (LSM) and optical coherent tomography (OCT) are the most promising methods for this application. Using these methods, the analysis of different skin parameters like dryness and oiliness of the skin, the barrier function and the structure of furrows and wrinkles are discussed. Additionally the homogeneity of distribution of topically applied creams, as well as their penetration into the skin were investigated. It is shown that these methods are highly valuable in dermatology for diagnostic and therapy control and for basic research, for instance in the field of structure analysis of hair follicles and sweat glands. The vertical images of the tissue produced by OCT can be easily compared with histological sections. Unfortunately, the resolution of the OCT technique is not high enough to carry out measurements on a cellular level, as is possible by LSM. LSM has the advantage that it can be used for the investigation of penetration and storage processes of topically applied substances, if these substances have fluorescent properties or if they are fluorescent-labelled.

  2. Non invasive tools for the diagnosis of liver cirrhosis.

    PubMed

    Soresi, Maurizio; Giannitrapani, Lydia; Cervello, Melchiorre; Licata, Anna; Montalto, Giuseppe

    2014-12-28

    Liver cirrhosis (LC), the end stage of many forms of chronic hepatitis of different etiologies is a diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules surrounded by annular fibrosis. This chronic progressive clinical condition, leads to liver cell failure and portal hypertension, which can favour the onset of hepatocellular carcinoma. Defining the phase of the natural history is crucial for therapeutic choice and prognosis. Liver biopsy is currently considered the best available standard of reference but it has some limits, so alternative tools have been developed to substitute liver biopsy when assessing liver fibrosis. Serum markers offer a cost-effective alternative to liver biopsy being less invasive and theoretically without complications. They can be classified into direct and indirect markers which may be used alone or in combination to produce composite scores. Diagnostic imaging includes a number of instruments and techniques to estimate liver fibrosis and cirrhosis like ultrasound (US), US Doppler, contrast enhanced US and Elastography. US could be used for the diagnosis of advanced LC while is not able to evaluate progression of fibrosis, in this case Elastography is more reliable. This review aims to revise the most recent data from the literature about non invasive methods useful in defining liver fibrosis.

  3. Preliminary results of a non-invasive method to measure tumor size and distribution in vivo

    PubMed Central

    Fu, Shu-Ling; Chen, Chien-An; Hung, Ling-Chien; Lee, Moon-Sing; Chiou, Wen-Yen; Lin, Hon-Yi; Su, Yu-Chieh; Lee, Ching-Chih; Hung, Shih-Kai

    2016-01-01

    Molecular imaging of reporter gene expression in cancer cells can provide rapid, sensitive and non-invasive monitoring of tumor behavior. The aim of the present study was to establish a non-invasive method to measure tumor size and distribution in vivo. Briefly, H-Ras-transformed cells were stably transfected with a plasmid containing the luciferase gene (Luc), designated as Ras/Luc. Ras/Luc cells were injected into the back or tail vein of nude BALB/cAnN-Foxn1nu/CrlNarl mice (age, 6–8 weeks). Mice were subsequently administered D-luciferin via intra-peritoneal injection, prior to image acquisition. Photons emitted from the mice were detected via an imaging system. Tumor size and distribution in vivo were quantified as photons/second. Andrographolide has demonstrated radiosensitization in previous in vitro and in vivo studies. In the present study, the potential effects of andrographolide cancer metastasis were investigated further, using an imaging system. Preliminary results of andrographolide combined with radiation indicated the inhibition of cancer metastasis. The present mechanistic study of andrographolide-mediated effects demonstrated that activated extracellular signal regulated kinase protein and H2O2 production levels were significantly increased by andrographolide. In summary, the present study established a non-invasive method to measure tumor size and distribution in vivo and indicated that andrographolide may be a potential therapeutic strategy in cancer therapy. PMID:28105095

  4. Non-invasive pressure difference estimation from PC-MRI using the work-energy equation

    PubMed Central

    Donati, Fabrizio; Figueroa, C. Alberto; Smith, Nicolas P.; Lamata, Pablo; Nordsletten, David A.

    2015-01-01

    Pressure difference is an accepted clinical biomarker for cardiovascular disease conditions such as aortic coarctation. Currently, measurements of pressure differences in the clinic rely on invasive techniques (catheterization), prompting development of non-invasive estimates based on blood flow. In this work, we propose a non-invasive estimation procedure deriving pressure difference from the work-energy equation for a Newtonian fluid. Spatial and temporal convergence is demonstrated on in silico Phase Contrast Magnetic Resonance Image (PC-MRI) phantoms with steady and transient flow fields. The method is also tested on an image dataset generated in silico from a 3D patient-specific Computational Fluid Dynamics (CFD) simulation and finally evaluated on a cohort of 9 subjects. The performance is compared to existing approaches based on steady and unsteady Bernoulli formulations as well as the pressure Poisson equation. The new technique shows good accuracy, robustness to noise, and robustness to the image segmentation process, illustrating the potential of this approach for non-invasive pressure difference estimation. PMID:26409245

  5. Non-invasive evaluation of facial crestal bone with ultrasonography

    PubMed Central

    Sinjab, Khaled; Chung, Ming-Pang; Chiang, Yi-Chen; Wang, Hom-Lay; Giannobile, William V.; Kripfgans, Oliver D.

    2017-01-01

    Purpose Facial crestal bone level and dimension determine function and esthetics of dentition and dental implants. We have previously demonstrated that ultrasound can identify bony and soft tissue structures in the oral cavity. The aim of this study is to evaluate the accuracy of using ultrasound to measure facial crestal bone level and thickness. Materials and methods A commercially available medical ultrasound scanner, paired with a 14 MHz imaging probe was used to scan dental and periodontal tissues at the mid-facial site of each tooth on 6 fresh cadavers. The alveolar crest level in relation to the cemento-enamel junction and its thickness on ultrasound images were measured and compared to those on cone-beam computed tomography (CBCT) scans and/or direct measurements on a total of 144 teeth. Results The mean crestal bone level measured by means of ultrasound, CBCT and direct measures was 2.66 ± 0.86 mm, 2.51 ± 0.82 mm, and 2.71 ± 1.04 mm, respectively. The mean crestal bone thickness was 0.71 ± 0.44 mm and 0.74 ± 0.34 mm, measured by means of ultrasound and CBCT, respectively. The correlations of the ultrasound readings to the other two methods were between 0.78 and 0.88. The mean absolute differences in crestal bone height and thickness between ultrasound and CBCT were 0.09 mm (-1.20 to 1.00 mm, p = 0.06) and 0.03 mm (-0.48 to 0.54 mm, p = 0.03), respectively. Conclusion Ultrasound was as accurate in determining alveolar bone level and its thickness as CBCT and direct measurements. Clinical trials will be required to further validate this non-ionizing and non-invasive method for determining facial crestal bone position and dimension. PMID:28178323

  6. Non-invasive femoropopliteal assessment: is that angiogram really necessary?

    PubMed Central

    Shearman, C P; Gwynn, B R; Curran, F; Gannon, M X; Simms, M H

    1986-01-01

    A method of non-invasive preoperative assessment of chronically ischaemic legs was developed that used clinical data and data derived from Doppler ultrasonography to produce a numerical score that could be compared with an angiographic score for stenosis of the popliteal artery trifurcation. The two scoring systems were applied retrospectively to 144 legs after femorodistal bypass. A close correlation was observed (r = 0.89, p less than 0.001), and both systems tended to predict the level of grafting undertaken. A prospective comparison was then made in 81 ischaemic legs that were examined by arteriography; the correlation between the two scoring systems remained close (r = 0.89, p less than 0.001), and the level of bypass was correctly predicted by the non-invasive assessment in 44 of 50 legs that were operated on. Use of the non-invasive assessment subsequently greatly reduced the indications for preoperative arteriography in patients requiring femorodistal vascular reconstruction. PMID:3094784

  7. Fatal brain gas embolism during non-invasive positive pressure ventilation

    PubMed Central

    Rivara, Claire B; Chevrolet, Jean-Claude; Gasche, Yvan; Charbonney, Emmanuel

    2008-01-01

    Gas embolism is a dreaded complication following invasive medical procedures, traumatic lung injury and decompression accidents. We report a case of fatal gas embolism following the use of non-invasive ventilation (NIV) with bilevel positive airway pressure (BiPAP). The patient initially underwent left bronchial artery embolisation for massive haemoptysis in the context of severe tuberculotic sequels. Under NIV and after heavy coughing he became hemiparetic and his level of consciousness suddenly dropped. Computed tomography of the brain showed multiple air embolism and ischaemic lesions were confirmed by magnetic resonance imaging. Echocardiographic investigations showed no intracardiac defect. Vasculo-pulmonary abnormalities in the context of heavy coughing and non-invasive ventilation may have played a major role in the occurrence of this event. New neurological events in a patient with tuberculotic sequels or any known vascular pulmonary abnormalities and NIV should raise the suspicion of brain gas embolism. PMID:21716825

  8. Limitations and opportunities of non-invasive liver stiffness measurement in children

    PubMed Central

    Engelmann, Guido; Quader, Jasmin; Teufel, Ulrike; Schenk, Jens Peter

    2017-01-01

    Changes in liver structure are an important issue in chronic hepatopathies. Until the end of the 20th century, these changes could only be determined by histological analyses of a liver specimen obtained via biopsy. The well-known limitations of this technique (i.e., pain, bleeding and the need for sedation) have precluded its routine use in follow-up of patients with liver diseases. However, the introduction of non-invasive technologies, such as ultrasound and magnetic resonance imaging, for measurement of liver stiffness as an indirect marker of fibroses has changed this situation. Today, several non-invasive tools are available to physicians to estimate the degree of liver fibrosis by analysing liver stiffness. This review describes the currently available tools for liver stiffness determination that are applicable to follow-up of liver fibrosis/cirrhosis with established clinical use in children, and discusses their features in comparison to the “historical” tools. PMID:28357028

  9. Non-invasive determination of the complete elastic moduli of spider silks

    NASA Astrophysics Data System (ADS)

    Koski, Kristie J.; Akhenblit, Paul; McKiernan, Keri; Yarger, Jeffery L.

    2013-03-01

    Spider silks possess nature’s most exceptional mechanical properties, with unrivalled extensibility and high tensile strength. Unfortunately, our understanding of silks is limited because the complete elastic response has never been measured—leaving a stark lack of essential fundamental information. Using non-invasive, non-destructive Brillouin light scattering, we obtain the entire stiffness tensors (revealing negative Poisson’s ratios), refractive indices, and longitudinal and transverse sound velocities for major and minor ampullate spider silks: Argiope aurantia, Latrodectus hesperus, Nephila clavipes, Peucetia viridans. These results completely quantify the linear elastic response for all possible deformation modes, information unobtainable with traditional stress-strain tests. For completeness, we apply the principles of Brillouin imaging to spatially map the elastic stiffnesses on a spider web without deforming or disrupting the web in a non-invasive, non-contact measurement, finding variation among discrete fibres, junctions and glue spots. Finally, we provide the stiffness changes that occur with supercontraction.

  10. An Acetone Nanosensor For Non-invasive Diabetes Detection

    NASA Astrophysics Data System (ADS)

    Wang, L.; Yun, X.; Stanacevic, M.; Gouma, P. I.

    2009-05-01

    Diabetes is a most common disease worldwide. Acetone in exhaled breath is a known biomarker of Type- 1 diabetes. An exhaled breath analyzer has been developed with the potential to diagnose diabetes as a non-invasive alternative of the currently used blood-based diagnostics. This device utilizes a chemiresistor based on ferroelectric tungsten oxide nanoparticles and detects acetone selectively in breath-simulated media. Real-time monitoring of the acetone concentration is feasible, potentially making this detector a revolutionary, non- invasive, diabetes diagnostic tool.

  11. Non-invasive brain stimulation in early rehabilitation after stroke.

    PubMed

    Blesneag, A V; Popa, L; Stan, A D

    2015-01-01

    The new tendency in rehabilitation involves non-invasive tools that, if applied early after stroke, promote neurorecovery. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may correct the disruption of cortical excitability and effectively contribute to the restoration of movement and speech. The present paper analyses the results of non-invasive brain stimulation (NIBS) trials, highlighting different aspects related to the repetitive transcranial magnetic stimulation frequency, transcranial direct current stimulation polarity, the period and stimulation places in acute and subacute ischemic strokes. The risk of adverse events, the association with motor or language recovery specific training, and the cumulative positive effect evaluation are also discussed.

  12. Non-invasive Thrombolysis using Microtripsy: A Parameter Study

    PubMed Central

    Zhang, Xi; Jin, Lifang; Vlaisavljevich, Eli; Owens, Gabe E.; Gurm, Hitinder S.; Cain, Charles A.; Xu, Zhen

    2016-01-01

    Histotripsy fractionates soft tissue by well-controlled acoustic cavitation using microsecond-long, high-intensity ultrasound pulses. The feasibility of using histotripsy as a non-invasive, drug-free, and image-guided thrombolysis method has been shown previously. A new histotripsy approach, termed Microtripsy, has recently been investigated for the thrombolysis application to improve treatment accuracy and avoid potential vessel damage. In this study, we investigated the effects of pulse repetition frequency (PRF) on microtripsy thrombolysis. Microtripsy thrombolysis treatments using different PRFs (5, 50, and 100 Hz) and doses (20, 50, and 100 pulses) were performed on blood clots in an in vitro vessel flow model. To quantitatively evaluate the microtripsy thrombolysis effect, the location of focal cavitation, the incident rate of pre-focal cavitation on the vessel wall, the size and location of the resulting flow channel, and the generated clot debris particles were measured. The results demonstrated that focal cavitation was always well-confined in the vessel lumen without contacting the vessel wall for all PRFs. Pre-focal cavitation on the front vessel wall was never observed at 5Hz PRF, but occasionally observed at PRFs of 50 Hz (1.2%) and 100 Hz (5.4%). However, the observed pre-focal cavitation was weak and didn’t significantly impact the focal cavitation. Results further demonstrated that, although the extent of clot fractionation per pulse was the highest at 5 Hz PRF at the beginning of treatment (<20 pulses), 100 Hz PRF generated the largest flow channels with a much shorter treatment time. Finally, results showed fewer large debris particles were generated at a higher PRF. Overall, the results of this study suggest that a higher PRF (50 or 100 Hz) may be a better choice for microtripsy thrombolysis to use clinically due to the larger resulting flow channel, shorter treatment time, and smaller debris particles. PMID:26670850

  13. Management of pediatric radiation dose using GE fluoroscopic equipment.

    PubMed

    Belanger, Barry; Boudry, John

    2006-09-01

    In this article, we present GE Healthcare's design philosophy and implementation of X-ray imaging systems with dose management for pediatric patients, as embodied in its current radiography and fluoroscopy and interventional cardiovascular X-ray product offerings. First, we present a basic framework of image quality and dose in the context of a cost-benefit trade-off, with the development of the concept of imaging dose efficiency. A set of key metrics of image quality and dose efficiency is presented, including X-ray source efficiency, detector quantum efficiency (DQE), detector dynamic range, and temporal response, with an explanation of the clinical relevance of each. Second, we present design methods for automatically selecting optimal X-ray technique parameters (kVp, mA, pulse width, and spectral filtration) in real time for various clinical applications. These methods are based on an optimization scheme where patient skin dose is minimized for a target desired image contrast-to-noise ratio. Operator display of skin dose and Dose-Area Product (DAP) is covered, as well. Third, system controls and predefined protocols available to the operator are explained in the context of dose management and the need to meet varying clinical procedure imaging demands. For example, fluoroscopic dose rate is adjustable over a range of 20:1 to adapt to different procedure requirements. Fourth, we discuss the impact of image processing techniques upon dose minimization. In particular, two such techniques, dynamic range compression through adaptive multiband spectral filtering and fluoroscopic noise reduction, are explored in some detail. Fifth, we review a list of system dose-reduction features, including automatic spectral filtration, virtual collimation, variable-rate pulsed fluoroscopic, grid and no-grid techniques, and fluoroscopic loop replay with store. In addition, we describe a new feature that automatically minimizes the patient-to-detector distance, along with an

  14. Non-invasive activation of optogenetic actuators

    NASA Astrophysics Data System (ADS)

    Birkner, Elisabeth; Berglund, Ken; Klein, Marguerita E.; Augustine, George J.; Hochgeschwender, Ute

    2014-03-01

    The manipulation of genetically targeted neurons with light (optogenetics) continues to provide unprecedented avenues into studying the function of the mammalian brain. However, potential translation into the clinical arena faces a number of significant hurdles, foremost among them the need for insertion of optical fibers into the brain to deliver light to opsins expressed on neuronal membranes. In order to overcome these hardware-related problems, we have developed an alternative strategy for delivering light to opsins which does not involve fiber implants. Rather, the light is produced by a protein, luciferase, which oxidizes intravenously applied substrate, thereby emitting bioluminescence. In proof-ofprinciple studies employing a fusion protein of a light-generating luciferase to a light-sensing opsin (luminopsin), we showed that light emitted by Gaussia luciferase is indeed able to activate channelrhodopsin, allowing modulation of neuronal activity when expressed in cultured neurons. Here we assessed applicability of the concept in vivo in mice expressing luminopsins from viral vectors and from genetically engineered transgenes. The experiments demonstrate that intravenously applied substrate reaches neurons in the brain, causing the luciferase to produce bioluminescence which can be imaged in vivo, and that activation of channelrhodopsin by bioluminescence is sufficient to affect behavior. Further developments of such technology based on combining optogenetics with bioluminescence - i.e. combining lightsensing molecules with biologically produced light through luciferases - should bring optogenetics closer to clinical applications.

  15. Automated quantification of lumbar vertebral kinematics from dynamic fluoroscopic sequences

    NASA Astrophysics Data System (ADS)

    Camp, Jon; Zhao, Kristin; Morel, Etienne; White, Dan; Magnuson, Dixon; Gay, Ralph; An, Kai-Nan; Robb, Richard

    2009-02-01

    We hypothesize that the vertebra-to-vertebra patterns of spinal flexion and extension motion of persons with lower back pain will differ from those of persons who are pain-free. Thus, it is our goal to measure the motion of individual lumbar vertebrae noninvasively from dynamic fluoroscopic sequences. Two-dimensional normalized mutual information-based image registration was used to track frame-to-frame motion. Software was developed that required the operator to identify each vertebra on the first frame of the sequence using a four-point "caliper" placed at the posterior and anterior edges of the inferior and superior end plates of the target vertebrae. The program then resolved the individual motions of each vertebra independently throughout the entire sequence. To validate the technique, 6 cadaveric lumbar spine specimens were potted in polymethylmethacrylate and instrumented with optoelectric sensors. The specimens were then placed in a custom dynamic spine simulator and moved through flexion-extension cycles while kinematic data and fluoroscopic sequences were simultaneously acquired. We found strong correlation between the absolute flexionextension range of motion of each vertebra as recorded by the optoelectric system and as determined from the fluoroscopic sequence via registration. We conclude that this method is a viable way of noninvasively assessing twodimensional vertebral motion.

  16. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, Richard M.; Packer, Samuel

    1984-01-01

    There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

  17. Non-invasive method of measuring cerebral spinal fluid pressure

    NASA Technical Reports Server (NTRS)

    Borchert, Mark S. (Inventor); Lambert, James L. (Inventor)

    2000-01-01

    The invention provides a method of non-invasively determining intracranial pressure from measurements of an eye. A parameter of an optic nerve of the eye is determined, along with an intraocular pressure of the eye. The intracranial pressure may be determined from the intraocular pressure and the parameter.

  18. Eyeblink Conditioning: A Non-Invasive Biomarker for Neurodevelopmental Disorders

    ERIC Educational Resources Information Center

    Reeb-Sutherland, Bethany C.; Fox, Nathan A.

    2015-01-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition,…

  19. [Non-invasive ventilation and acute cardiogenic pulmonary oedema].

    PubMed

    Golmard, Céline

    2015-11-01

    Non-invasive ventilation is an integral part of therapies used in patients presenting acute cardiogenic pulmonary oedema. In cardiac intensive care, these patients are treated by teams trained and practised in this technique. The nurses play a central role in the support and monitoring of the patients.

  20. Non-invasive treatment options for focal cortical dysplasia

    PubMed Central

    WANG, TING-TING; ZHOU, DONG

    2016-01-01

    Focal cortical dysplasia (FCD) presents a strong clinical challenge especially for the treatment of the associated epilepsy. Epilepsy in FCD is often treatment-resistant and constitutes 50% of treatment-resistant cases. Antiepileptic drugs (AEDs) have been widely used in the treatment of FCD. However, evidence to suggest their specific effect on the treatment of FCD remains to be established. In view of this resistance, several alternative treatments have been suggested. Although treatment currently involves surgical management, non-invasive treatments have been identified. The aim of the present review, was to assess non-invasive management strategies including, i) mammalian target of rapamycin (mTOR) inhibitors, ii) ketogenic diet (KD), and iii) vagus nerve stimulation (VNS). In addition, we discussed the literature available regarding the use of AEDs in FCD. Experiments conducted with mammals detailing rapamycin gene mutations in FCD have produced vital information for exploring treatment options using mTOR inhibitors. Of note is the importance of KD in children with FCD. This diet has been shown to modify disease progression by attenuating chromatin modification, a master regulator for gene expression and functional adaptation of the cell. FCD has also been studied widely with neurostimulation techniques. The outcomes of these techniques have been found to be variable. For widespread dysplasias, VNS has been shown to produce responder rates of >50%. Nevertheless, non-invasive cranial nerve stimulation techniques such as transcutaneous VNS and non-invasive VNS are gaining better patient compatibility, albeit their efficacy remains to be established. PMID:27168769

  1. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, R.M.; Packer, S.

    1984-10-30

    An apparatus and method is disclosed for diagnosing ocular cancer that is both non-invasive and accurate. The apparatus comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67. 2 figs.

  2. Non-invasive in vivo measurement of macular carotenoids

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2009-01-01

    A non-invasive in vivo method for assessing macular carotenoids includes performing Optical Coherence Tomography (OCT) on a retina of a subject. A spatial representation of carotenoid levels in the macula based on data from the OCT of the retina can be generated.

  3. Non-invasive Markers of Liver Fibrosis: Adjuncts or Alternatives to Liver Biopsy?

    PubMed Central

    Chin, Jun L.; Pavlides, Michael; Moolla, Ahmad; Ryan, John D.

    2016-01-01

    Liver fibrosis reflects sustained liver injury often from multiple, simultaneous factors. Whilst the presence of mild fibrosis on biopsy can be a reassuring finding, the identification of advanced fibrosis is critical to the management of patients with chronic liver disease. This necessity has lead to a reliance on liver biopsy which itself is an imperfect test and poorly accepted by patients. The development of robust tools to non-invasively assess liver fibrosis has dramatically enhanced clinical decision making in patients with chronic liver disease, allowing a rapid and informed judgment of disease stage and prognosis. Should a liver biopsy be required, the appropriateness is clearer and the diagnostic yield is greater with the use of these adjuncts. While a number of non-invasive liver fibrosis markers are now used in routine practice, a steady stream of innovative approaches exists. With improvement in the reliability, reproducibility and feasibility of these markers, their potential role in disease management is increasing. Moreover, their adoption into clinical trials as outcome measures reflects their validity and dynamic nature. This review will summarize and appraise the current and novel non-invasive markers of liver fibrosis, both blood and imaging based, and look at their prospective application in everyday clinical care. PMID:27378924

  4. Non-invasive hemodynamic assessment of aortic coarctation: validation with in vivo measurements.

    PubMed

    Itu, Lucian; Sharma, Puneet; Ralovich, Kristóf; Mihalef, Viorel; Ionasec, Razvan; Everett, Allen; Ringel, Richard; Kamen, Ali; Comaniciu, Dorin

    2013-04-01

    We propose a CFD-based approach for the non-invasive hemodynamic assessment of pre- and post-operative coarctation of aorta (CoA) patients. Under our approach, the pressure gradient across the coarctation is determined from computational modeling based on physiological principles, medical imaging data, and routine non-invasive clinical measurements. The main constituents of our approach are a reduced-order model for computing blood flow in patient-specific aortic geometries, a parameter estimation procedure for determining patient-specific boundary conditions and vessel wall parameters from non-invasive measurements, and a comprehensive pressure-drop formulation coupled with the overall reduced-order model. The proposed CFD-based algorithm is fully automatic, requiring no iterative tuning procedures for matching the computed results to observed patient data, and requires approximately 6-8 min of computation time on a standard personal computer (Intel Core2 Duo CPU, 3.06 GHz), thus making it feasible for use in a clinical setting. The initial validation studies for the pressure-drop computations have been performed on four patient datasets with native or recurrent coarctation, by comparing the results with the invasively measured peak pressure gradients recorded during routine cardiac catheterization procedure. The preliminary results are promising, with a mean absolute error of less than 2 mmHg in all the patients.

  5. Visual event-related potentials of dogs: a non-invasive electroencephalography study.

    PubMed

    Törnqvist, Heini; Kujala, Miiamaaria V; Somppi, Sanni; Hänninen, Laura; Pastell, Matti; Krause, Christina M; Kujala, Jan; Vainio, Outi

    2013-11-01

    Previously, social and cognitive abilities of dogs have been studied within behavioral experiments, but the neural processing underlying the cognitive events remains to be clarified. Here, we employed completely non-invasive scalp-electroencephalography in studying the neural correlates of the visual cognition of dogs. We measured visual event-related potentials (ERPs) of eight dogs while they observed images of dog and human faces presented on a computer screen. The dogs were trained to lie still with positive operant conditioning, and they were neither mechanically restrained nor sedated during the measurements. The ERPs corresponding to early visual processing of dogs were detectable at 75-100 ms from the stimulus onset in individual dogs, and the group-level data of the 8 dogs differed significantly from zero bilaterally at around 75 ms at the most posterior sensors. Additionally, we detected differences between the responses to human and dog faces in the posterior sensors at 75-100 ms and in the anterior sensors at 350-400 ms. To our knowledge, this is the first illustration of completely non-invasively measured visual brain responses both in individual dogs and within a group-level study, using ecologically valid visual stimuli. The results of the present study validate the feasibility of non-invasive ERP measurements in studies with dogs, and the study is expected to pave the way for further neurocognitive studies in dogs.

  6. A non-invasive head-holding device for chronic neural recordings in awake behaving monkeys

    PubMed Central

    Amemori, Satoko; Amemori, Ken-ichi; Cantor, Margaret L.; Graybiel, Ann M.

    2014-01-01

    Background We have developed a novel head-holding device for behaving non-human primates that affords stability suitable for reliable chronic electrophysiological recording experiments. The device is completely non-invasive, and thus avoids the risk of infection and other complications that can occur with the use of conventional, surgically implanted head-fixation devices. New method The device consists of a novel non-invasive head mold and bar clamp holder, and is customized to the shape of each monkey’s head. The head-holding device that we introduce, combined with our recording system and reflection-based eye-tracking system, allows for chronic behavioral experiments and single-electrode or multi-electrode recording, as well as manipulation of brain activity. Results and comparison with existing methods With electrodes implanted chronically in multiple brain regions, we could record neural activity from cortical and subcortical structures with stability equal to that recorded with conventional head-post fixation. Consistent with the non-invasive nature of the device, we could record neural signals for more than two years with a single implant. Importantly, the monkeys were able to hold stable eye fixation positions while held by this device, demonstrating the possibility of analyzing eye movement data with only the gentle restraint imposed by the non-invasive head-holding device. Conclusions We show that the head-holding device introduced here can be extended to the head holding of smaller animals, and note that it could readily be adapted for magnetic resonance brain imaging over extended periods of time. PMID:25448381

  7. Non-invasive, non-radiological quantification of anteroposterior knee joint ligamentous laxity

    PubMed Central

    Russell, D. F.; Deakin, A. H.; Fogg, Q. A.; Picard, F.

    2013-01-01

    Objectives We performed in vitro validation of a non-invasive skin-mounted system that could allow quantification of anteroposterior (AP) laxity in the outpatient setting. Methods A total of 12 cadaveric lower limbs were tested with a commercial image-free navigation system using trackers secured by bone screws. We then tested a non-invasive fabric-strap system. The lower limb was secured at 10° intervals from 0° to 60° of knee flexion and 100 N of force was applied perpendicular to the tibia. Acceptable coefficient of repeatability (CR) and limits of agreement (LOA) of 3 mm were set based on diagnostic criteria for anterior cruciate ligament (ACL) insufficiency. Results Reliability and precision within the individual invasive and non-invasive systems was acceptable throughout the range of flexion tested (intra-class correlation coefficient 0.88, CR 1.6 mm). Agreement between the two systems was acceptable measuring AP laxity between full extension and 40° knee flexion (LOA 2.9 mm). Beyond 40° of flexion, agreement between the systems was unacceptable (LOA > 3 mm). Conclusions These results indicate that from full knee extension to 40° flexion, non-invasive navigation-based quantification of AP tibial translation is as accurate as the standard validated commercial system, particularly in the clinically and functionally important range of 20° to 30° knee flexion. This could be useful in diagnosis and post-operative evaluation of ACL pathology. Cite this article: Bone Joint Res 2013;2:233–7. PMID:24184443

  8. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  9. Non Invasive Assessment of Tissue Oxygenation and Blood Flow as a Tool for Staging Diabetes

    NASA Astrophysics Data System (ADS)

    Sujatha, N.; Anand, B. S. Suresh; Jayanthy, A. K.; Murthy, V. B. Narayana; Sheshadri; Poddar, Richa

    2011-10-01

    Diffuse reflectance spectroscopy and laser speckle imaging have been identified as an effective tool in characterizing/assessing tissue oxygenation and blood flow in real time tissues. In this paper we are exploring the possibility of finding out blood flow/oxygenation at different areas of feet of subjects with different levels of diabetes. Tissue blood flow is determined by assessing the contrast variations in the laser speckle image of the foot and tissue oxygenation is assessed by diffuse reflectance spectroscopy. A combination of both techniques offers an effective and purely non invasive mode of examination in the staging of Diabetes.

  10. A non-invasive approach to monitor chronic lymphocytic leukemia engraftment in a xenograft mouse model using ultra-small superparamagnetic iron oxide-magnetic resonance imaging (USPIO-MRI).

    PubMed

    Valdora, Francesca; Cutrona, Giovanna; Matis, Serena; Morabito, Fortunato; Massucco, Carlotta; Emionite, Laura; Boccardo, Simona; Basso, Luca; Recchia, Anna Grazia; Salvi, Sandra; Rosa, Francesca; Gentile, Massimo; Ravina, Marco; Pace, Daniele; Castronovo, Angela; Cilli, Michele; Truini, Mauro; Calabrese, Massimo; Neri, Antonino; Neumaier, Carlo Emanuele; Fais, Franco; Baio, Gabriella; Ferrarini, Manlio

    2016-11-01

    Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia among adults. Despite its indolent nature, CLL remains an incurable disease. Herein we aimed to monitor CLL disease engraftment and, progression/regression in a xenograft CLL mouse model using ultra-small superparamagnetic iron oxide-magnetic resonance imaging (USPIO-MRI). Spleen contrast enhancement, quantified as percentage change in signal intensity upon USPIO administration, demonstrated a difference due to a reduced USPIO uptake, in the spleens of mice injected with CLL cells (NSG-CLL, n=71) compared to controls (NSG-CTR, n=17). These differences were statistically significant both after 2 and 4weeks from CLL cells injection. In addition comparison of mice treated with rituximab with untreated controls for changes in spleen iron uptake confirmed that it is possible to monitor treatment efficacy in this mouse model of CLL using USPIO-enhanced MRI. Further applications could include the preclinical in vivo monitoring of new therapies and the clinical evaluation of CLL patients.

  11. Non-invasive computer-assisted measurement of knee alignment.

    PubMed

    Clarke, Jon V; Riches, Philip E; Picard, Frederic; Deakin, Angela H

    2012-01-01

    The quantification of knee alignment is a routine part of orthopaedic practice and is important for monitoring disease progression, planning interventional strategies, and follow-up of patients. Currently available technologies such as radiographic measurements have a number of drawbacks. The aim of this study was to validate a potentially improved technique for measuring knee alignment under different conditions. An image-free navigation system was adapted for non-invasive use through the development of external infrared tracker mountings. Stability was assessed by comparing the variance (F-test) of repeated mechanical femoro-tibial (MFT) angle measurements for a volunteer and a leg model. MFT angles were then measured supine, standing and with varus-valgus stress in asymptomatic volunteers who each underwent two separate registrations and repeated measurements for each condition. The mean difference and 95% limits of agreement were used to assess intra-registration and inter-registration repeatability. For multiple registrations the range of measurements for the external mountings was 1° larger than for the rigid model with statistically similar variance (p=0.34). Thirty volunteers were assessed (19 males, 11 females) with a mean age of 41 years (range: 20-65) and a mean BMI of 26 (range: 19-34). For intra-registration repeatability, consecutive coronal alignment readings agreed to almost ±1°, with up to ±0.5° loss of repeatability for coronal alignment measured before and after stress maneuvers, and a ±0.2° loss following stance trials. Sagittal alignment measurements were less repeatable overall by an approximate factor of two. Inter-registration agreement limits for coronal and sagittal supine MFT angles were ±1.6° and ±2.3°, respectively. Varus and valgus stress measurements agreed to within ±1.3° and ±1.1°, respectively. Agreement limits for standing MFT angles were ±2.9° (coronal) and ±5.0° (sagittal), which may have reflected a variation

  12. Non-invasive microsensors for studying cell/tissue physiology

    NASA Astrophysics Data System (ADS)

    Vanegas, D. C.; Taguchi, M.; Chaturvedi, P.; Burrs, S.; McLamore, E. S.

    2013-05-01

    Non-invasive tools that allow real-time quantification of molecules relevant to metabolism, homeostasis, and cell signaling in cells and tissue are of great importance for studying physiology. Several microsensor technologies have been developed to monitor concentration of molecules such as ions, oxygen, electroactive molecules (e.g., nitric oxide, hydrogen peroxide), and biomolecules (e.g., sugars, hormones). The major challenges for microsensors are overcoming relatively low sensitivity and low signal-to-noise ratio. Modern approaches for enhancing microsensor performance focus on the incorporation of catalytic nanomaterials to increase sensitivity, reduce response time, and increase operating range. To improve signal-to-noise ratio, a non-invasive microsensor modality called self-referencing (SR) is being applied. The SR technique allows measurement of temporal and spatial transport dynamics at the cell, tissue, organ, and organismal level.

  13. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    PubMed Central

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm Jr., Martin C.; Austen Jr., William G.; Yarmush, Martin L.

    2015-01-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases. PMID:25965851

  14. Skin rejuvenation with non-invasive pulsed electric fields.

    PubMed

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P; Albadawi, Hassan; Felix Broelsch, G; Watkins, Michael T; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C; Austen, William G; Yarmush, Martin L

    2015-05-12

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  15. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    NASA Astrophysics Data System (ADS)

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C., Jr.; Austen, William G., Jr.; Yarmush, Martin L.

    2015-05-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  16. Non-Invasive Blood Flow Monitoring on the Wrist

    DTIC Science & Technology

    2007-11-02

    INVASIVE BLOOD FLOW MONITORING ON THE WRIST M. Maier, L-G. Lindberg Department of Biomedical Engineering , University of Linköping, Sweden The Swedish...Department of Biomedical Engineering . This study was supported by The Swedish Competence Center of Non-invasive Medical Measurements NIMED...Element Number Author(s) Project Number Task Number Work Unit Number Performing Organization Name(s) and Address(es) Department of Biomedical

  17. SQUID magnetometry applied as non-invasive electroanalytic chemical technique

    SciTech Connect

    Jette, B.D.; MacVicar, M.L.A. )

    1991-03-01

    This paper reports on a SQUID magnetometer, employed as a highly sensitive ammeter, used to perform standard electroanalytic chemical measurements non- invasively. Specifically, the magnetic fields generated by the net ionic movement in the solution of a driven electrochemical system is detected by the gradiometer coils. The SQUID signal can then be compared to conventional current measurements. One such standard measurement investigated is Cyclic Voltametry (CV) which determines the I-V characteristics of an electrochemical system yielding critical kinetic parameters.

  18. NOTE: A feasibility study of markerless fluoroscopic gating for lung cancer radiotherapy using 4DCT templates

    NASA Astrophysics Data System (ADS)

    Li, Ruijiang; Lewis, John H.; Cerviño, Laura I.; Jiang, Steve B.

    2009-10-01

    A major difficulty in conformal lung cancer radiotherapy is respiratory organ motion, which may cause clinically significant targeting errors. Respiratory-gated radiotherapy allows for more precise delivery of prescribed radiation dose to the tumor, while minimizing normal tissue complications. Gating based on external surrogates is limited by its lack of accuracy, while gating based on implanted fiducial markers is limited primarily by the risk of pneumothorax due to marker implantation. Techniques for fluoroscopic gating without implanted fiducial markers (markerless gating) have been developed. These techniques usually require a training fluoroscopic image dataset with marked tumor positions in the images, which limits their clinical implementation. To remove this requirement, this study presents a markerless fluoroscopic gating algorithm based on 4DCT templates. To generate gating signals, we explored the application of three similarity measures or scores between fluoroscopic images and the reference 4DCT template: un-normalized cross-correlation (CC), normalized cross-correlation (NCC) and normalized mutual information (NMI), as well as average intensity (AI) of the region of interest (ROI) in the fluoroscopic images. Performance was evaluated using fluoroscopic and 4DCT data from three lung cancer patients. On average, gating based on CC achieves the highest treatment accuracy given the same efficiency, with a high target coverage (average between 91.9% and 98.6%) for a wide range of nominal duty cycles (20-50%). AI works well for two patients out of three, but failed for the third patient due to interference from the heart. Gating based on NCC and NMI usually failed below 50% nominal duty cycle. Based on this preliminary study with three patients, we found that the proposed CC-based gating algorithm can generate accurate and robust gating signals when using 4DCT reference template. However, this observation is based on results obtained from a very limited

  19. CT fluoroscopic guided insertion of inferior vena cava filters.

    PubMed

    Ignotus, P; Wetton, C; Berry, J

    2006-03-01

    The value and use of inferior vena cava (IVC) filters is well documented and has been growing since the first reported filter placement in 1973 and the first percutaneous insertion in 1982. Access routes now include both jugular veins, both ante-cubital veins and both femoral veins. However, all insertions require some form of imaging, usually fluoroscopy, to identify the location of the filter with respect to the IVC and the renal veins. We describe two cases where the patients' weight was significantly greater than the weight limit of the angiography table, necessitating insertion under CT fluoroscopic guidance.

  20. Invasive and non-invasive assessment of portal hypertension.

    PubMed

    Leung, Jonathan Chung-Fai; Loong, Thomson Chi-Wang; Pang, James; Wei, Jeremy Lok; Wong, Vincent Wai-Sun

    2017-03-30

    Portal hypertension is the central driver of complications in patients with chronic liver diseases and cirrhosis. The diagnosis of portal hypertension has important prognostic and clinical implications. In particular, screening for varices in patients with portal hypertension can effectively reduce the morbidity and mortality of variceal bleeding. In this article, we review the invasive and non-invasive methods to assess portal hypertension. Hepatic venous pressure gradient remains the gold standard to measure portal pressure but is invasive and seldom performed outside expert centers and research settings. In recent years, a number of non-invasive tests of fibrosis have shown good correlation with liver histology. They also show promise in identifying patients with portal hypertension and large varices. As a result, the latest Baveno VI consensus guidelines endorse the use of liver stiffness measurement by transient elastography and platelet count as initial assessment to select patients for varices screening. On the other hand, the performance of non-invasive tests in assessing the response to non-selective beta-blockers or transjugular intrahepatic portosystemic shunting is either suboptimal or unclear.

  1. Method for non-invasively recording electrocardiograms in conscious mice

    PubMed Central

    Chu, Victor; Otero, Jose M; Lopez, Orlando; Morgan, James P; Amende, Ivo; Hampton, Thomas G

    2001-01-01

    Background The rapid increase in the development of mouse models is resulting in a growing demand for non-invasive physiological monitoring of large quantities of mice. Accordingly, we developed a new system for recording electrocardiograms (ECGs) in conscious mice without anesthesia or implants, and created Internet-accessible software for analyzing murine ECG signals. The system includes paw-sized conductive electrodes embedded in a platform configured to record ECGs when 3 single electrodes contact 3 paws. Results With this technique we demonstrated significantly reduced heart rate variability in neonates compared to adult mice. We also demonstrated that female mice exhibit significant ECG differences in comparison to age-matched males, both at baseline and in response to β-adrenergic stimulation. Conclusions The technology we developed enables non-invasive screening of large numbers of mice for ECG changes resulting from genetic, pharmacological, or pathophysiological alterations. Data we obtained non-invasively are not only consistent with what have been reported using invasive and expensive methods, but also demonstrate new findings regarding gender-dependent and age-dependent variations in ECGs in mice. PMID:11476671

  2. Non invasive assessment of the human tear film dynamics.

    PubMed

    Ring, M H; Rabensteiner, D F; Horwath-Winter, J; Boldin, I; Schrödl, F; Reitsamer, H; Haslwanter, T

    2015-11-01

    Dry eye disease, or keratoconjunctivitis sicca, is a multifactorial syndrome with altered tear film homeostasis leading to ocular irritations. These alterations cause discomfort and stress for the patient, but only a few objective parameters allow for proper differential diagnosis into different subtypes of this condition. The mostly invasively performed standard assessment procedures for tear film diagnosis are manifold, but often correlate quite poorly with the subjectively reported symptoms. Due to the inherent limitations, e.g. the subjectivity of the commonly performed invasive tests, a number of devices have been developed to assess the human tear film non-invasively. Since the production, delivery, distribution and drainage of the tear film is a dynamic process, we have focused our review on non-invasive methods which are capable of continuous or repetitive observations of the tear film during an inter-blink interval. These dynamic methods include (1) Interferometry, (2) Pattern Projection, (3) Aberrometry, (4) Thermography; and (5) Evaporimetry. These techniques are discussed with respect to their diagnostic value, both for screening and differential diagnostic of Dry Eye Disease. Many of the parameters obtained from these tests have been shown to have the potential to reliably discriminate patients from healthy subjects, especially when the tests are performed automatically and objectively. The differentiation into subtypes based solely on a single, dynamic parameter may not be feasible, but the combination of non-invasively performed procedures may provide good discrimination results.

  3. Deconstructing autofluorescence: non-invasive detection and monitoring of biochemistry in cells and tissues (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Goldys, Ewa M.; Gosnell, Martin E.; Anwer, Ayad G.; Cassano, Juan C.; Sue, Carolyn M.; Mahbub, Saabah B.; Pernichery, Sandeep M.; Inglis, David W.; Adhikary, Partho P.; Jazayeri, Jalal A.; Cahill, Michael A.; Saad, Sonia; Pollock, Carol; Sutton-Mcdowall, Melanie L.; Thompson, Jeremy G.

    2016-03-01

    Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous fluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from imaging of native fluorescence has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Multispectral intrinsic fluorescence imaging was applied to patient olfactory neurosphere-derived cells, cell model of a human metabolic disease MELAS (mitochondrial myopathy, encephalomyopathy, lactic acidosis, stroke-like syndrome). By using an endogenous source of contrast, subtle metabolic variations have been detected between living cells in their full morphological context which made it possible to distinguish healthy from diseased cells before and after therapy. Cellular maps of native fluorophores, flavins, bound and free NADH and retinoids unveiled subtle metabolic signatures and helped uncover significant cell subpopulations, in particular a subpopulation with compromised mitochondrial function. The versatility of our method is further illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent.

  4. Review of biomedical optical imaging—a powerful, non-invasive, non-ionizing technology for improving in vivo diagnosis

    NASA Astrophysics Data System (ADS)

    Balas, Costas

    2009-10-01

    This paper reviews the recent developments in the field of biomedical optical imaging, emphasizing technologies that have been moved from 'bench top to bedside'. Important new developments in this field allow for unprecedented visualization of the tissue microstructure and enable quantitative mapping of disease-specific endogenous and exogenous substances. With these advances, optical imaging technologies are becoming powerful clinical tools for non-invasive and objective diagnosis, guided treatment and monitoring therapies. Recent developments in visible and infrared diffuse spectroscopy and imaging, spectral imaging, optical coherence tomography, confocal imaging, molecular imaging and dynamic spectral imaging are presented together with their derivative medical devices. Their perspectives and challenges are discussed.

  5. Multiphoton excited hemoglobin fluorescence and third harmonic generation for non-invasive microscopy of stored blood

    PubMed Central

    Saytashev, Ilyas; Glenn, Rachel; Murashova, Gabrielle A.; Osseiran, Sam; Spence, Dana; Evans, Conor L.; Dantus, Marcos

    2016-01-01

    Red blood cells (RBC) in two-photon excited fluorescence (TPEF) microscopy usually appear as dark disks because of their low fluorescent signal. Here we use 15fs 800nm pulses for TPEF, 45fs 1060nm pulses for three-photon excited fluorescence, and third harmonic generation (THG) imaging. We find sufficient fluorescent signal that we attribute to hemoglobin fluorescence after comparing time and wavelength resolved spectra of other expected RBC endogenous fluorophores: NADH, FAD, biliverdin, and bilirubin. We find that both TPEF and THG microscopy can be used to examine erythrocyte morphology non-invasively without breaching a blood storage bag. PMID:27699111

  6. Non-invasive cardiac mapping in clinical practice: Application to the ablation of cardiac arrhythmias.

    PubMed

    Dubois, Rémi; Shah, Ashok J; Hocini, Mélèze; Denis, Arnaud; Derval, Nicolas; Cochet, Hubert; Sacher, Frédéric; Bear, Laura; Duchateau, Josselin; Jais, Pierre; Haissaguerre, Michel

    2015-01-01

    Ten years ago, electrocardiographic imaging (ECGI) started to demonstrate its efficiency in clinical settings. The initial application to localize focal ventricular arrhythmias such as ventricular premature beats was probably the easiest to challenge and validates the concept. Our clinical experience in using this non-invasive mapping technique to identify the sources of electrical disorders and guide catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats) and ventricular pre-excitation (Wolff-Parkinson-White syndrome) is described here.

  7. [Amyotrophic neuralgia associated with bilateral phrenic paralysis treated with non-invasive mechanical ventilation].

    PubMed

    García García, María Del Carmen; Hernández Borge, Jacinto; Antona Rodríguez, María José; Pires Gonçalves, Pedro; García García, Gema

    2015-09-07

    Amyotrophic neuralgia is an uncommon neuropathy characterized by severe unilateral shoulder pain. Isolated or concomitant involvement of other peripheral motor nerves depending on the brachial plexus such as phrenic or laryngeal nerves is unusual(1). Its etiology is unknown, yet several explanatory factors have been proposed. Phrenic nerve involvement, either unilateral or bilateral, is exceedingly rare. Diagnosis relies on anamnesis, functional and imaging investigations and electromyogram. We report the case of a 48-year-old woman with a past history of renal transplantation due to proliferative glomerulonephritis with subsequent transplant rejection, who was eventually diagnosed with amyotrophic neuralgia with bilateral phrenic involvement, and who required sustained non-invasive mechanical ventilation.

  8. Three-dimensional curvilinear device reconstruction from two fluoroscopic views

    NASA Astrophysics Data System (ADS)

    Delmas, Charlotte; Berger, Marie-Odile; Kerrien, Erwan; Riddell, Cyril; Trousset, Yves; Anxionnat, René; Bracard, Serge

    2015-03-01

    In interventional radiology, navigating devices under the sole guidance of fluoroscopic images inside a complex architecture of tortuous and narrow vessels like the cerebral vascular tree is a difficult task. Visualizing the device in 3D could facilitate this navigation. For curvilinear devices such as guide-wires and catheters, a 3D reconstruction may be achieved using two simultaneous fluoroscopic views, as available on a biplane acquisition system. The purpose of this paper is to present a new automatic three-dimensional curve reconstruction method that has the potential to reconstruct complex 3D curves and does not require a perfect segmentation of the endovascular device. Using epipolar geometry, our algorithm translates the point correspondence problem into a segment correspondence problem. Candidate 3D curves can be formed and evaluated independently after identifying all possible combinations of compatible 3D segments. Correspondence is then inherently solved by looking in 3D space for the most coherent curve in terms of continuity and curvature. This problem can be cast into a graph problem where the most coherent curve corresponds to the shortest path of a weighted graph. We present quantitative results of curve reconstructions performed from numerically simulated projections of tortuous 3D curves extracted from cerebral vascular trees affected with brain arteriovenous malformations as well as fluoroscopic image pairs of a guide-wire from both phantom and clinical sets. Our method was able to select the correct 3D segments in 97.5% of simulated cases thus demonstrating its ability to handle complex 3D curves and can deal with imperfect 2D segmentation.

  9. Non-invasive measurements of tissue hemodynamics with hybrid diffuse optical methods

    NASA Astrophysics Data System (ADS)

    Durduran, Turgut

    Diffuse optical techniques were used to measure hemodynamics of tissues non-invasively. Spectroscopy and tomography of the brain, muscle and implanted tumors were carried out in animal models and humans. Two qualitatively different methods, diffuse optical tomography and diffuse correlation tomography, were hybridized permitting simultaneous measurement of total hemoglobin concentration, blood oxygen saturation and blood flow. This combination of information was processed further to derive estimates of oxygen metabolism (e.g. CMRO 2) in tissue. The diffuse correlation measurements of blood flow were demonstrated in human tissues, for the first time, demonstrating continous, non-invasive imaging of oxygen metabolism in large tissue volumes several centimeters below the tissue surface. The bulk of these investigations focussed on cerebral hemodynamics. Extensive validation of this methodology was carried out in in vivo rat brain models. Three dimensional images of deep tissue hemodynamics in middle cerebral artery occlusion and cortical spreading depression (CSD) were obtained. CSD hemodynamics were found to depend strongly on partial pressure of carbon dioxide. The technique was then adapted for measurement of human brain. All optical spectroscopic measurements of CMRO2 during functional activation were obtained through intact human skull non-invasively. Finally, a high spatio-temporal resolution measurement of cerebral blood flow due to somatosensory cortex activation following electrical forepaw stimulation in rats was carried out with laser speckle flowmetry. New analysis methods were introduced for laser speckle flowmetry. In other organs, deep tissue hemodynamics were measured on human calf muscle during exercise and cuff-ischemia and were shown to have some clinical utility for peripheral vascular disease. In mice tumor models, the measured hemodynamics were shown to be predictive of photodynamic therapy efficacy, again suggesting promise of clinical utility

  10. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines

    PubMed Central

    Busschots, Steven; O’Toole, Sharon; O’Leary, John J.; Stordal, Britta

    2014-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. • Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner. • The technique is quick, affordable and eliminates sample manipulation. • The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines. PMID:26150966

  11. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines.

    PubMed

    Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

    2015-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. •Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner.•The technique is quick, affordable and eliminates sample manipulation.•The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines.

  12. Quantitative non-invasive cell characterisation and discrimination based on multispectral autofluorescence features

    PubMed Central

    Gosnell, Martin E.; Anwer, Ayad G.; Mahbub, Saabah B.; Menon Perinchery, Sandeep; Inglis, David W.; Adhikary, Partho P.; Jazayeri, Jalal A.; Cahill, Michael A.; Saad, Sonia; Pollock, Carol A.; Sutton-McDowall, Melanie L.; Thompson, Jeremy G.; Goldys, Ewa M.

    2016-01-01

    Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous autofluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from autofluorescence imaging has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent. Label-free classifications are validated by the analysis of Classification Determinant (CD) antigen expression. The versatility of our method is illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos. PMID:27029742

  13. New Jersey's Thomas Edison and the fluoroscope.

    PubMed

    Tselos, G D

    1995-11-01

    Thomas Edison played a major role in the development of early x-ray technology in 1896, notably increasing tube power and reliability and making the fluoroscope a practical instrument. Eventually, Edison would move x-ray technology from the laboratory to the marketplace.

  14. Non-Invasive Detection of Early Retinal Neuronal Degeneration by Ultrahigh Resolution Optical Coherence Tomography

    PubMed Central

    Tudor, Debbie; Kajić, Vedran; Rey, Sara; Erchova, Irina; Považay, Boris; Hofer, Bernd; Powell, Kate A.; Marshall, David; Rosin, Paul L.; Drexler, Wolfgang; Morgan, James E.

    2014-01-01

    Optical coherence tomography (OCT) has revolutionises the diagnosis of retinal disease based on the detection of microscopic rather than subcellular changes in retinal anatomy. However, currently the technique is limited to the detection of microscopic rather than subcellular changes in retinal anatomy. However, coherence based imaging is extremely sensitive to both changes in optical contrast and cellular events at the micrometer scale, and can generate subtle changes in the spectral content of the OCT image. Here we test the hypothesis that OCT image speckle (image texture) contains information regarding otherwise unresolvable features such as organelle changes arising in the early stages of neuronal degeneration. Using ultrahigh resolution (UHR) OCT imaging at 800 nm (spectral width 140 nm) we developed a robust method of OCT image analyses, based on spatial wavelet and texture-based parameterisation of the image speckle pattern. For the first time we show that this approach allows the non-invasive detection and quantification of early apoptotic changes in neurons within 30 min of neuronal trauma sufficient to result in apoptosis. We show a positive correlation between immunofluorescent labelling of mitochondria (a potential source of changes in cellular optical contrast) with changes in the texture of the OCT images of cultured neurons. Moreover, similar changes in optical contrast were also seen in the retinal ganglion cell- inner plexiform layer in retinal explants following optic nerve transection. The optical clarity of the explants was maintained throughout in the absence of histologically detectable change. Our data suggest that UHR OCT can be used for the non-invasive quantitative assessment of neuronal health, with a particular application to the assessment of early retinal disease. PMID:24776961

  15. Instrumentation for Non-Invasive Assessment of Cardiovascular Regulation

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J.

    1999-01-01

    It is critically important to be able to assess alterations in cardiovascular regulation during and after space flight. We propose to develop an instrument for the non-invasive assessment of such alterations that can be used on the ground and potentially during space flight. This instrumentation would be used by the Cardiovascular Alterations Team at multiple sites for the study of the effects of space flight on the cardiovascular system and the evaluation of countermeasures. In particular, the Cardiovascular Alterations Team will use this instrumentation in conjunction with ground-based human bed-rest studies and during application of acute stresses e.g., tilt, lower body negative pressure, and exercise. In future studies, the Cardiovascular Alterations Team anticipates using this instrumentation to study astronauts before and after space flight and ultimately, during space flight. The instrumentation may also be used by the Bone Demineralization/Calcium Metabolism Team, the Neurovestibular Team and the Human Performance Factors, Sleep and Chronobiology Team to measure changes in autonomic nervous function. The instrumentation will be based on a powerful new technology - cardiovascular system identification (CSI) - which has been developed in our laboratory. CSI provides a non-invasive approach for the study of alterations in cardiovascular regulation. This approach involves the analysis of second-to-second fluctuations in physiologic signals such as heart rate and non-invasively measured arterial blood pressure in order to characterize quantitatively the physiologic mechanisms responsible for the couplings between these signals. Through the characterization of multiple physiologic mechanisms, CSI provides a closed-loop model of the cardiovascular regulatory state in an individual subject.

  16. Non-invasive techniques for determining musculoskeleton body composition

    SciTech Connect

    Cohn, S.H.

    1984-01-01

    In vivo neutron activation analysis, combined with gamma spectrometry, has ushered in a new era of clinical diagnosis and evaluation of therapies, as well as investigation into and modelling of body composition in both normal individuals and patients suffering from various diseases and dysfunctions. Body composition studies have provided baseline data on such vital constituents as nitrogen, potassium and calcium. The non-invasive measurement techniques are particularly suitable for study of the musculo-skeletal changes in body composition. Of particular relevance here is the measurement of calcium loss in astronauts during prolonged space flights.

  17. Non-invasive pulmonary function test on Morquio patients.

    PubMed

    Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G; Theroux, Mary; Bober, Michael B; Oldham, Helen M; Orii, Tadao; Shaffer, Thomas H

    2015-08-01

    In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and

  18. Towards a smart non-invasive fluid loss measurement system.

    PubMed

    Suryadevara, N K; Mukhopadhyay, S C; Barrack, L

    2015-04-01

    In this article, a smart wireless sensing non-invasive system for estimating the amount of fluid loss, a person experiences while physical activity is presented. The system measures three external body parameters, Heart Rate, Galvanic Skin Response (GSR, or skin conductance), and Skin Temperature. These three parameters are entered into an empirically derived formula along with the user's body mass index, and estimation for the amount of fluid lost is determined. The core benefit of the developed system is the affluence usage in combining with smart home monitoring systems to care elderly people in ambient assisted living environments as well in automobiles to monitor the body parameters of a motorist.

  19. Optical coherence tomography: a non-invasive technique applied to conservation of paintings

    NASA Astrophysics Data System (ADS)

    Liang, Haida; Gomez Cid, Marta; Cucu, Radu; Dobre, George; Kudimov, Boris; Pedro, Justin; Saunders, David; Cupitt, John; Podoleanu, Adrian

    2005-06-01

    It is current practice to take tiny samples from a painting to mount and examine in cross-section under a microscope. However, since conservation practice and ethics limit sampling to a minimum and to areas along cracks and edges of paintings, which are often unrepresentative of the whole painting, results from such analyses cannot be taken as representative of a painting as a whole. Recently in a preliminary study, we have demonstrated that near-infrared Optical Coherence Tomography (OCT) can be used directly on paintings to examine the cross-section of paint and varnish layers without contact and the need to take samples. OCT is an optical interferometric technique developed for in vivo imaging of the eye and biological tissues; it is essentially a scanning Michelson's interferometer with a "broad-band" source that has the spatial coherence of a laser. The low temporal coherence and high spatial concentration of the source are the keys to high depth resolution and high sensitivity 3D imaging. The technique is non-invasive and non-contact with a typical working distance of 2 cm. This non-invasive technique enables cross-sections to be examined anywhere on a painting. In this paper, we will report new results on applying near-infrared en-face OCT to paintings conservation and extend the application to the examination of underdrawings, drying processes, and quantitative measurements of optical properties of paint and varnish layers.

  20. Non-invasive health status detection system using Gabor filters based on facial block texture features.

    PubMed

    Shu, Ting; Zhang, Bob

    2015-04-01

    Blood tests allow doctors to check for certain diseases and conditions. However, using a syringe to extract the blood can be deemed invasive, slightly painful, and its analysis time consuming. In this paper, we propose a new non-invasive system to detect the health status (Healthy or Diseased) of an individual based on facial block texture features extracted using the Gabor filter. Our system first uses a non-invasive capture device to collect facial images. Next, four facial blocks are located on these images to represent them. Afterwards, each facial block is convolved with a Gabor filter bank to calculate its texture value. Classification is finally performed using K-Nearest Neighbor and Support Vector Machines via a Library for Support Vector Machines (with four kernel functions). The system was tested on a dataset consisting of 100 Healthy and 100 Diseased (with 13 forms of illnesses) samples. Experimental results show that the proposed system can detect the health status with an accuracy of 93 %, a sensitivity of 94 %, a specificity of 92 %, using a combination of the Gabor filters and facial blocks.

  1. Chromatibody, a novel non-invasive molecular tool to explore and manipulate chromatin in living cells

    PubMed Central

    Jullien, Denis; Vignard, Julien; Fedor, Yoann; Béry, Nicolas; Olichon, Aurélien; Crozatier, Michèle; Erard, Monique; Cassard, Hervé; Ducommun, Bernard; Salles, Bernard

    2016-01-01

    ABSTRACT Chromatin function is involved in many cellular processes, its visualization or modification being essential in many developmental or cellular studies. Here, we present the characterization of chromatibody, a chromatin-binding single-domain, and explore its use in living cells. This non-intercalating tool specifically binds the heterodimer of H2A–H2B histones and displays a versatile reactivity, specifically labeling chromatin from yeast to mammals. We show that this genetically encoded probe, when fused to fluorescent proteins, allows non-invasive real-time chromatin imaging. Chromatibody is a dynamic chromatin probe that can be modulated. Finally, chromatibody is an efficient tool to target an enzymatic activity to the nucleosome, such as the DNA damage-dependent H2A ubiquitylation, which can modify this epigenetic mark at the scale of the genome and result in DNA damage signaling and repair defects. Taken together, these results identify chromatibody as a universal non-invasive tool for either in vivo chromatin imaging or to manipulate the chromatin landscape. PMID:27206857

  2. Clinical role of non-invasive assessment of portal hypertension.

    PubMed

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-07

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field.

  3. Influence of hemoglobin on non-invasive optical bilirubin sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Gong, Qiliang; Zou, Da; Xu, Kexin

    2012-03-01

    Since the abnormal metabolism of bilirubin could lead to diseases in the human body, especially the jaundice which is harmful to neonates. Traditional invasive measurements are difficult to be accepted by people because of pain and infection. Therefore, the real-time and non-invasive measurement of bilirubin is of great significance. However, the accuracy of currently transcutaneous bilirubinometry(TcB) is generally not high enough, and affected by many factors in the human skin, mostly by hemoglobin. In this talk, absorption spectra of hemoglobin and bilirubin have been collected and analyzed, then the Partial Least Squares (PLS) models have been built. By analyzing and comparing the Correlation and Root Mean Square Error of Prediction(RMSEP), the results show that the Correlation of bilirubin solution model is larger than that of the mixture solution added with hemoglobin, and its RMSEP value is smaller than that of mixture solution. Therefore, hemoglobin has influences on the non-invasive optical bilirubin sensing. In next step, it is necessary to investigate how to eliminate the influence.

  4. Modulation of Untruthful Responses with Non-Invasive Brain Stimulation

    PubMed Central

    Fecteau, Shirley; Boggio, Paulo; Fregni, Felipe; Pascual-Leone, Alvaro

    2013-01-01

    Deceptive abilities have long been studied in relation to personality traits. More recently, studies explored the neural substrates associated with deceptive skills suggesting a critical role of the prefrontal cortex. Here we investigated whether non-invasive brain stimulation over the dorsolateral prefrontal cortex (DLPFC) could modulate generation of untruthful responses about subject’s personal life across contexts (i.e., deceiving on guilt-free questions on daily activities; generating previously memorized lies about past experience; and producing spontaneous lies about past experience), as well as across modality responses (verbal and motor responses). Results reveal that real, but not sham, transcranial direct current stimulation (tDCS) over the DLPFC can reduce response latency for untruthful over truthful answers across contexts and modality responses. Also, contexts of lies seem to incur a different hemispheric laterality. These findings add up to previous studies demonstrating that it is possible to modulate some processes involved in generation of untruthful answers by applying non-invasive brain stimulation over the DLPFC and extend these findings by showing a differential hemispheric contribution of DLPFCs according to contexts. PMID:23550273

  5. Clinical role of non-invasive assessment of portal hypertension

    PubMed Central

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-01

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field. PMID:28104976

  6. Evolving strategies for liver fibrosis staging: Non-invasive assessment

    PubMed Central

    Stasi, Cristina; Milani, Stefano

    2017-01-01

    Transient elastography and the acoustic radiation force impulse techniques may play a pivotal role in the study of liver fibrosis. Some studies have shown that elastography can detect both the progression and regression of fibrosis. Similarly, research results have been analysed and direct and indirect serum markers of hepatic fibrosis have shown high diagnostic accuracy for advanced fibrosis/cirrhosis. The prognosis of different stages of cirrhosis is well established and various staging systems have been proposed, largely based on clinical data. However, it is still unknown if either non-invasive markers of liver fibrosis or elastography may contribute to a more accurate staging of liver cirrhosis, in terms of prognosis and fibrosis regression after effective therapy. In fact, not enough studies have shown both the fibrosis regression in different cirrhosis stages and the point beyond which the prognosis does not change - even in the event of fibrosis regression. Therefore, future studies are needed to validate non-invasive methods in predicting the different phases of liver cirrhosis. PMID:28127192

  7. Visual memory improved by non-invasive brain stimulation.

    PubMed

    Chi, Richard P; Fregni, Felipe; Snyder, Allan W

    2010-09-24

    Our visual memories are susceptible to errors, but less so in people who have a more literal cognitive style. This inspired us to attempt to improve visual memory with non-invasive brain stimulation. We applied 13 min of bilateral transcranial direct current stimulation (tDCS) to the anterior temporal lobes. Our stimulation protocol included 3 conditions, each with 12 neurotypical participants: (i) left cathodal stimulation together with right anodal stimulation, (ii) left anodal stimulation together with right cathodal stimulation, and (iii) sham (control) stimulation. Only participants who received left cathodal stimulation (decrease in excitability) together with right anodal stimulation (increase in excitability) showed an improvement in visual memory. This 110% improvement in visual memory was similar to the advantage people with autism, who are known to be more literal, show over normal people in the identical visual task. Importantly, participants receiving stimulation of the opposite polarity (left anodal together with right cathodal stimulation) failed to show any change in memory performance. This is the first demonstration that visual memory can be enhanced in healthy people using non-invasive brain stimulation.

  8. TU-F-12A-01: Quantitative Non-Linear Compartment Modeling of 89Zr- and 124I- Labeled J591 Monoclonal Antibody Kinetics Using Serial Non-Invasive Positron Emission Tomography Imaging in a Pre-Clinical Human Prostate Cancer Mouse Model

    SciTech Connect

    Fung, EK; Cheal, SM; Chalasani, S; Fareedy, SB; Punzalan, B; Humm, JL; Osborne, JR; Larson, SM; Zanzonico, PB; Otto, B; Bander, NH

    2014-06-15

    Purpose: To examine the binding kinetics of human IgG monoclonal antibody J591 which targets prostate-specific membrane antigen (PSMA) in a pre-clinical mouse cancer model using quantitative PET compartmental analysis of two radiolabeled variants. Methods: PSMA is expressed in normal human prostate, and becomes highly upregulated in prostate cancer, making it a promising therapeutic target. Two forms of J591, radiolabeled with either {sup 89}Zr or {sup 124}I, were prepared. {sup 89}Zr is a radiometal that becomes trapped in the cell upon internalization by the antigen-antibody complex, while radioiodine leaves the cell. Mice with prostate cancer xenografts underwent non-invasive serial imaging on a Focus 120 microPET up to 144 hours post-injection of J591. A non-linear compartmental model describing the binding and internalization of antibody in tumor xenograft was developed and applied to the PET-derived time-activity curves. The antibody-antigen association rate constant (ka), total amount of antigen per gram tumor (Ag-total), internalization rate of antibody-antigen complex, and efflux rate of radioisotope from tumor were fitted using the model. The surface-bound and the internalized activity were also estimated. Results: Values for ka, Ag-total, and internalization rate were found to be similar regardless of radiolabel payload used. The efflux rate, however, was ∼ 9-fold higher for {sup 124}I-J591 than for {sup 89}Zr-J591. Time-dependent surface-bound and internalized radiotracer activity were similar for both radiolabels at early times post-injection, but clearly differed beyond 24 hours. Conclusion: Binding and internalization of J591 to PSMA-expressing tumor xenografts were similar when radiolabeled with either {sup 89}Zr or {sup 124}I payload. The difference in efflux of radioactivity from tumor may be attributable to differential biological fate intracellularly of the radioisotopes. This has great significance for radioimmunotherapy and antibody

  9. Order of magnitude reduction of fluoroscopic x-ray dose

    NASA Astrophysics Data System (ADS)

    Bal, Abhinav; Robert, Normand; Machan, Lindsay; Deutsch, Meir; Kisselgoff, David; Babyn, Paul; Rowlands, John A.

    2012-03-01

    The role of fluoroscopic imaging is critical for diagnostic and image guided therapy. However, fluoroscopic imaging can require significant radiation leading to increased cancer risk and non-stochastic effects such as radiation burns. Our purpose is to reduce the exposure and dose to the patient by an order of magnitude in these procedures by use of the region of interest method. Method and Materials: Region of interest fluoroscopy (ROIF) uses a partial attenuator. The central region of the image has full exposure while the image periphery, there to provide context only, has a reduced exposure rate. ROIF using a static partial attenuator has been shown in our previous studies to reduce the dose area product (DAP) to the patient by at least 2.5 times. Significantly greater reductions in DAP would require improvements in flat panel detectors performance at low x-ray exposures or a different x-ray attenuation strategy. Thus we have investigated a second, dynamic, approach. We have constructed an x-ray shutter system allowing a normal x-ray exposure in the region of interest while reducing the number of x-ray exposures in the periphery through the rapid introduction, positioning and removal of an x-ray attenuating shutter to block radiation only for selected frames. This dynamic approach eliminates the DQE(0) loss associated with the use of static partial attenuator applied to every frame thus permitting a greater reduction in DAP. Results: We have compared the two methods by modeling and determined their fundamental limits.

  10. A rapid, non-invasive procedure for quantitative assessment of drought survival using chlorophyll fluorescence

    PubMed Central

    Woo, Nick S; Badger, Murray R; Pogson, Barry J

    2008-01-01

    Background Analysis of survival is commonly used as a means of comparing the performance of plant lines under drought. However, the assessment of plant water status during such studies typically involves detachment to estimate water shock, imprecise methods of estimation or invasive measurements such as osmotic adjustment that influence or annul further evaluation of a specimen's response to drought. Results This article presents a procedure for rapid, inexpensive and non-invasive assessment of the survival of soil-grown plants during drought treatment. The changes in major photosynthetic parameters during increasing water deficit were monitored via chlorophyll fluorescence imaging and the selection of the maximum efficiency of photosystem II (Fv/Fm) parameter as the most straightforward and practical means of monitoring survival is described. The veracity of this technique is validated through application to a variety of Arabidopsis thaliana ecotypes and mutant lines with altered tolerance to drought or reduced photosynthetic efficiencies. Conclusion The method presented here allows the acquisition of quantitative numerical estimates of Arabidopsis drought survival times that are amenable to statistical analysis. Furthermore, the required measurements can be obtained quickly and non-invasively using inexpensive equipment and with minimal expertise in chlorophyll fluorometry. This technique enables the rapid assessment and comparison of the relative viability of germplasm during drought, and may complement detailed physiological and water relations studies. PMID:19014425

  11. Non-invasive biomarkers in pancreatic cancer diagnosis: what we need versus what we have

    PubMed Central

    Bujanda, Luis

    2016-01-01

    Pancreatic cancer (PC) is probably the most lethal tumor being forecast as the second most fatal cancer by 2020 in developed countries. Only the earliest forms of the disease are a curable disease but it has to be diagnosed before symptoms starts. Detection at curable phase demands screening intervention for early detection and differential diagnosis. Unfortunately, no successful strategy or image technique has been concluded as effective approach and currently non-invasive biomarkers are the hope. Multiple translational research studies have explored minimally or non-invasive biomarkers in biofluids-blood, urine, stool, saliva or pancreatic juice, but diagnostic performance has not been validated yet. Nowadays no biomarker, alone or in combination, has been superior to carbohydrate antigen 19-9 (CA19-9) in sensitivity and specificity. Although the number of novel biomarkers for early diagnosis of PC has been increasing during the last couple of years, no molecular signature is ready to be implemented in clinical routine. Under the uncertain future, miRNAs profiling and methylation status seem to be the most promising biomarkers. However, good results in larger validations are urgently needed before application. Industry efforts through biotech and pharmaceutical companies are urgently required to demonstrate accuracy and validate promising results from basic and translational results. PMID:27162784

  12. Real-time non-invasive detection of inhalable particulates delivered into live mouse airways.

    PubMed

    Donnelley, Martin; Morgan, Kaye S; Fouras, Andreas; Skinner, William; Uesugi, Kentaro; Yagi, Naoto; Siu, Karen K W; Parsons, David W

    2009-07-01

    Fine non-biological particles small enough to be suspended in the air are continually inhaled as we breathe. These particles deposit on airway surfaces where they are either cleared by airway defences or can remain and affect lung health. Pollutant particles from vehicles, building processes and mineral and industrial dusts have the potential to cause both immediate and delayed health problems. Because of their small size, it has not been possible to non-invasively examine how individual particles deposit on live airways, or to consider how they behave on the airway surface after deposition. In this study, synchrotron phase-contrast X-ray imaging (PCXI) has been utilized to detect and monitor individual particle deposition. The in vitro detectability of a range of potentially respirable particulates was first determined. Of the particulates tested, only asbestos, quarry dust, fibreglass and galena (lead sulfate) were visible in vitro. These particulates were then examined after delivery into the nasal airway of live anaesthetized mice; all were detectable in vivo but each exhibited different surface appearances and behaviour along the airway surface. The two fibrous particulates appeared as agglomerations enveloped by fluid, while the non-fibrous particulates were present as individual particles. Synchrotron PCXI provides the unique ability to non-invasively detect and track deposition of individual particulates in live mouse airways. With further refinement of particulate sizing and delivery techniques, PCXI should provide a novel approach for live animal monitoring of airway particulates relevant to lung health.

  13. Congenital coronary artery anomalies silent until geriatric age: non-invasive assessment, angiography tips, and treatment

    PubMed Central

    Rigatelli, Gianluca; Dell'Avvocata, Fabio; Van Tan, Nguyen; Daggubati, Rames; Nanijundappa, Aravinda

    2015-01-01

    Coronary artery anomalies (CAAs) may be discovered more often as incidental findings during the normal diagnostic process for other cardiac diseases or less frequently on the basis of manifestations of myocardial ischemia. The cardiovascular professional may be involved in their angiographic diagnosis, functional assessment and eventual endovascular treatment. A complete angiographic definition is mandatory in order to understand the functional effects and plan any intervention in CAAs: computed tomography and magnetic resonance imaging are useful non-invasive tools to detect three-dimensional morphology of the anomalies and its relationships with contiguous cardiac structures, whereas coronary arteriography remains the gold standard for a definitive anatomic picture. A practical idea of the possible functional significance is mandatory for deciding how to manage CAAs: non-invasive stress tests and in particular the invasive pharmacological stress tests with or without intravascular ultrasound monitoring can assess correctly the functional significance of the most CAAs. Finally, the knowledge of the particular endovascular techniques and material is of paramount importance for achieving technical and clinical success. CAAs represent a complex issue, which rarely involve the cardiovascular professional at different levels. A timely practical knowledge of the main issues regarding CAAs is important in the management of such entities. PMID:25678906

  14. Non-Invasive Investigation of Bone Adaptation in Humans to Cumulative Daily Mechanical Loading

    NASA Technical Reports Server (NTRS)

    Whalen, Robert; Cleek, Tammy; Sode, Miki

    2003-01-01

    The goal of our research is to better understand the functional relationship between cumulative daily skeletal loading generated by daily activity and the regulation of bone density and bone structure. We have proposed the calcaneus and tibia as useful model bone sites loaded by internal forces in equilibrium with the ground reaction force during gait. The daily history of the ground reaction force is a good relative measure of daily lower limb and calcaneal loading that can be compared to bone density and structure of the calcaneus and cross-sectional geometry of the tibia and fibula. Over the past several years, we have developed image-processing technologies to improve our ability to measure bone density and structure in the calcaneus and lower leg non-invasively with computed tomography and bone densitometry, or DXA. The objective of our current research effort is to determine the accuracy and precision of our CT and DXA image processing methods.

  15. The importance of optical methods for non-invasive measurements in the skin care industry

    NASA Astrophysics Data System (ADS)

    Stamatas, Georgios N.

    2010-02-01

    Pharmaceutical and cosmetic industries are concerned with treating skin disease, as well as maintaining and promoting skin health. They are dealing with a unique tissue that defines our body in space. As such, skin provides not only the natural boundary with the environment inhibiting body dehydration as well as penetration of exogenous aggressors to the body, it is also ideally situated for optical measurements. A plurality of spectroscopic and imaging methods is being used to understand skin physiology and pathology and document the effects of topically applied products on the skin. The obvious advantage of such methods over traditional biopsy techniques is the ability to measure the cutaneous tissue in vivo and non-invasively. In this work, we will review such applications of various spectroscopy and imaging methods in skin research that is of interest the cosmetic and pharmaceutical industry. Examples will be given on the importance of optical techniques in acquiring new insights about acne pathogenesis and infant skin development.

  16. Non-invasive cerebellar stimulation--a consensus paper.

    PubMed

    Grimaldi, G; Argyropoulos, G P; Boehringer, A; Celnik, P; Edwards, M J; Ferrucci, R; Galea, J M; Groiss, S J; Hiraoka, K; Kassavetis, P; Lesage, E; Manto, M; Miall, R C; Priori, A; Sadnicka, A; Ugawa, Y; Ziemann, U

    2014-02-01

    The field of neurostimulation of the cerebellum either with transcranial magnetic stimulation (TMS; single pulse or repetitive (rTMS)) or transcranial direct current stimulation (tDCS; anodal or cathodal) is gaining popularity in the scientific community, in particular because these stimulation techniques are non-invasive and provide novel information on cerebellar functions. There is a consensus amongst the panel of experts that both TMS and tDCS can effectively influence cerebellar functions, not only in the motor domain, with effects on visually guided tracking tasks, motor surround inhibition, motor adaptation and learning, but also for the cognitive and affective operations handled by the cerebro-cerebellar circuits. Verbal working memory, semantic associations and predictive language processing are amongst these operations. Both TMS and tDCS modulate the connectivity between the cerebellum and the primary motor cortex, tuning cerebellar excitability. Cerebellar TMS is an effective and valuable method to evaluate the cerebello-thalamo-cortical loop functions and for the study of the pathophysiology of ataxia. In most circumstances, DCS induces a polarity-dependent site-specific modulation of cerebellar activity. Paired associative stimulation of the cerebello-dentato-thalamo-M1 pathway can induce bidirectional long-term spike-timing-dependent plasticity-like changes of corticospinal excitability. However, the panel of experts considers that several important issues still remain unresolved and require further research. In particular, the role of TMS in promoting cerebellar plasticity is not established. Moreover, the exact positioning of electrode stimulation and the duration of the after effects of tDCS remain unclear. Future studies are required to better define how DCS over particular regions of the cerebellum affects individual cerebellar symptoms, given the topographical organization of cerebellar symptoms. The long-term neural consequences of non-invasive

  17. A holistic multimodal approach to the non-invasive analysis of watercolour paintings

    NASA Astrophysics Data System (ADS)

    Kogou, Sotiria; Lucian, Andrei; Bellesia, Sonia; Burgio, Lucia; Bailey, Kate; Brooks, Charlotte; Liang, Haida

    2015-11-01

    A holistic approach using non-invasive multimodal imaging and spectroscopic techniques to study the materials (pigments, drawing materials and paper) and painting techniques of watercolour paintings is presented. The non-invasive imaging and spectroscopic techniques include VIS-NIR reflectance spectroscopy and multispectral imaging, micro-Raman spectroscopy, X-ray fluorescence spectroscopy (XRF) and optical coherence tomography (OCT). The three spectroscopic techniques complement each other in pigment identification. Multispectral imaging (near-infrared bands), OCT and micro-Raman complement each other in the visualisation and identification of the drawing material. OCT probes the micro-structure and light scattering properties of the substrate, while XRF detects the elemental composition that indicates the sizing methods and the filler content. The multiple techniques were applied in a study of forty-six nineteenth-century Chinese export watercolours from the Victoria and Albert Museum (V&A) and the Royal Horticultural Society (RHS) to examine to what extent the non-invasive analysis techniques employed complement each other and how much useful information about the paintings can be extracted to address art conservation and history questions. A micro-destructive technique of micro-fade spectrometry was used to assess the vulnerability of the paintings to light exposure. Most of the paint and paper substrates were found to be more stable than ISO Blue Wool 3. The palette was found to be composed of mostly traditional Chinese pigments. While the synthetic pigment, Prussian blue, made in Europe, was found on some of the paintings, none was found on the RHS paintings accurately recorded as being between 1817 and 1831 even though it is known that Prussian blue was imported to China during this period. The scale insect dyes, lac and cochineal, were detected on nearly every painting including those that fall within the identified date range. Cochineal is known to have

  18. Fluoroscopic chest tube insertion and patient care.

    PubMed Central

    Collins, J. D.; Shaver, M. L.; Disher, A. C.; Miller, T. Q.

    1992-01-01

    Catheters and chest tubes may be placed under fluoroscopic control to reduce pleural effusions. This procedure has been adopted as a routine procedure at the UCLA School of Medicine in Los Angeles, California to improve patient care. This technique was modified for the placement of large chest tubes, which can be placed by a radiologist without multiple attempts or complications. Our experience with 2234 patients who underwent this procedure between 1977 and 1990 is described. PMID:1404463

  19. Non-Invasive Detection of Anaemia Using Digital Photographs of the Conjunctiva

    PubMed Central

    Collings, Shaun; Thompson, Oliver; Hirst, Evan; Goossens, Louise; George, Anup; Weinkove, Robert

    2016-01-01

    Background and Aims Anaemia is a major health burden worldwide. Although the finding of conjunctival pallor on clinical examination is associated with anaemia, inter-observer variability is high, and definitive diagnosis of anaemia requires a blood sample. We aimed to detect anaemia by quantifying conjunctival pallor using digital photographs taken with a consumer camera and a popular smartphone. Our goal was to develop a non-invasive screening test for anaemia. Patients and Methods The conjunctivae of haemato-oncology in- and outpatients were photographed in ambient lighting using a digital camera (Panasonic DMC-LX5), and the internal rear-facing camera of a smartphone (Apple iPhone 5S) alongside an in-frame calibration card. Following image calibration, conjunctival erythema index (EI) was calculated and correlated with laboratory-measured haemoglobin concentration. Three clinicians independently evaluated each image for conjunctival pallor. Results Conjunctival EI was reproducible between images (average coefficient of variation 2.96%). EI of the palpebral conjunctiva correlated more strongly with haemoglobin concentration than that of the forniceal conjunctiva. Using the compact camera, palpebral conjunctival EI had a sensitivity of 93% and 57% and specificity of 78% and 83% for detection of anaemia (haemoglobin < 110 g/L) in training and internal validation sets, respectively. Similar results were found using the iPhone camera, though the EI cut-off value differed. Conjunctival EI analysis compared favourably with clinician assessment, with a higher positive likelihood ratio for prediction of anaemia. Conclusions Erythema index of the palpebral conjunctiva calculated from images taken with a compact camera or mobile phone correlates with haemoglobin and compares favourably to clinician assessment for prediction of anaemia. If confirmed in further series, this technique may be useful for the non-invasive screening for anaemia. PMID:27070544

  20. SU-E-P-15: Technique Factor Modulation and Reference Plane Air Kerma Rates in Response to Simulated Patient Thickness Variations for a Sample of Current Generation Fluoroscopes

    SciTech Connect

    Wunderle, K; Rakowski, J; Dong, F

    2015-06-15

    Purpose: To evaluate and compare approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. Methods: A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and spectral filtration over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within a default abdomen or body imaging protocol. Results: The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. Some vendors have made hardware advances increasing the radiation output capabilities of their fluoroscopes; this was evident in the acquisition air kerma rates. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ copper filtration in the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Conclusion: Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and provides opportunities to optimize the imaging protocols for clinical practice. The enhanced radiation output capabilities of some of the fluoroscopes may, under specific conditions, may be beneficial; however, these higher output capabilities also have the potential to lead to unnecessarily high dose rates. Therefore, all parties involved in imaging, including the clinical team, medical physicists, and imaging vendors, must work

  1. Non-Invasive Tension Measurement Devices for Parachute Cordage

    NASA Technical Reports Server (NTRS)

    Litteken, Douglas A.; Daum, Jared S.

    2016-01-01

    The need for lightweight and non-intrusive tension measurements has arisen alongside the development of high-fidelity computer models of textile and fluid dynamics. In order to validate these computer models, data must be gathered in the operational environment without altering the design, construction, or performance of the test article. Current measurement device designs rely on severing a cord and breaking the load path to introduce a load cell. These load cells are very reliable, but introduce an area of high stiffness in the load path, directly affecting the structural response, adding excessive weight, and possibly altering the dynamics of the parachute during a test. To capture the required data for analysis validation without affecting the response of the system, non-invasive measurement devices have been developed and tested by NASA. These tension measurement devices offer minimal impact to the mass, form, fit, and function of the test article, while providing reliable, axial tension measurements for parachute cordage.

  2. Non-invasive ventilation in acute cardiogenic pulmonary oedema

    PubMed Central

    Agarwal, R; Aggarwal, A; Gupta, D; Jindal, S

    2005-01-01

    Non-invasive ventilation (NIV) is the delivery of assisted mechanical ventilation to the lungs, without the use of an invasive endotracheal airway. NIV has revolutionised the management of patients with various forms of respiratory failure. It has decreased the need for invasive mechanical ventilation and its attendant complications. Cardiogenic pulmonary oedema (CPO) is a common medical emergency, and NIV has been shown to improve both physiological and clinical outcomes. From the data presented herein, it is clear that there is sufficiently high level evidence to favour the use of continuous positive airway pressure (CPAP), and that the use of CPAP in patients with CPO decreases intubation rate and improves survival (number needed to treat seven and eight respectively). However, there is insufficient evidence to recommend the use of bilevel positive airway pressure (BiPAP), probably the exception being patients with hypercapnic CPO. More trials are required to conclusively define the role of BiPAP in CPO. PMID:16210459

  3. Moral Enhancement Using Non-invasive Brain Stimulation

    PubMed Central

    Darby, R. Ryan; Pascual-Leone, Alvaro

    2017-01-01

    Biomedical enhancement refers to the use of biomedical interventions to improve capacities beyond normal, rather than to treat deficiencies due to diseases. Enhancement can target physical or cognitive capacities, but also complex human behaviors such as morality. However, the complexity of normal moral behavior makes it unlikely that morality is a single capacity that can be deficient or enhanced. Instead, our central hypothesis will be that moral behavior results from multiple, interacting cognitive-affective networks in the brain. First, we will test this hypothesis by reviewing evidence for modulation of moral behavior using non-invasive brain stimulation. Next, we will discuss how this evidence affects ethical issues related to the use of moral enhancement. We end with the conclusion that while brain stimulation has the potential to alter moral behavior, such alteration is unlikely to improve moral behavior in all situations, and may even lead to less morally desirable behavior in some instances. PMID:28275345

  4. An inverse method for non-invasive viscosity measurements

    NASA Astrophysics Data System (ADS)

    Fullana, J.-M.; Dispot, N.; Flaud, P.; Rossi, M.

    2007-04-01

    A procedure is presented which allows to compute in a non-invasive manner, blood viscosity through flow measurements obtained at a fixed vessel cross-section. The data set is made of measurements (artery radius and spatially discrete velocity profiles) performed at given time intervals for which the signal to noise ratio is typical of U.S. Doppler velocimetry in clinical situation. This identification approach is based on the minimization, through a backpropagation algorithm, of a cost function quantifying the distance between numerical data obtained through Navier-Stokes simulations and experimental measurements. Since this cost function implicitly depends on the value of viscosity used in numerical simulations, its minimization determines an effective viscosity which is shown to be robust to measurement errors and sampling time. Such an approach is shown to work in an in vitro experiment, and seems to be suitable for in vivo measurements of viscosity by the atraumatic techniques of Doppler echography.

  5. Hybrid CARS for Non-Invasive Blood Glucose Monitoring

    NASA Astrophysics Data System (ADS)

    Wang, Xi; Pestov, Dmitry; Zhang, Aihua; Murawski, Robert; Sokolov, Alexei; Welch, George; Laane, Jaan; Scully, Marlan

    2007-10-01

    We develop a spectroscopy technique that combines the advantages of both the frequency-resolved coherent anti-Stokes Raman scattering (CARS) and the time-resolved CARS. We use broadband preparation pulses to get an instantaneous coherent excitation of multiplex molecular vibration levels and subsequent optically shaped time-delayed narrowband probing pulse to detect these vibrations. This technique can suppress the nonresonant background and retrieve the molecular fingerprint signal efficiently and rapidly. We employ this technique to glucose detection, the final goal of which is accurate, non-invasive (i.e. painless) and continuous monitoring of blood glucose concentration in the Diabetes diagnosis to replace the current glucose measurement process, which requires painful fingerpricks and therefore cannot be performed more than a few times a day. We have gotten the CARS spectra of glucose aqueous solution down to 2 mM.

  6. Non-invasive assessment of phonatory and respiratory dynamics.

    PubMed

    LaBlance, G R; Steckol, K F; Cooper, M H

    1991-10-01

    Evaluation of vocal pathology and the accompanying dysphonia should include an assessment of laryngeal structure and mobility as well as respiratory dynamics. Laryngeal structure is best observed through laryngoscopy which provides an accurate assessment of the tissues and their mobility. Respiratory measures of lung volume, air-flow and pressure, and breathing dynamics are typically determined via spirometry and pneumotachography. While the above are traditional invasive procedures which interfere with normal speech production, recent advances in electronic technology have resulted in the development of non-invasive procedures to assess phonatory and respiratory dynamics. These procedures, when used as an adjunct to laryngoscopy, can provide information that is useful in the diagnosis and management of vocal tract dysfunction. The Laryngograph and Computer-Aided Fluency Establishment Trainer, described here, are examples of this new technology.

  7. [Non-invasive brain stimulation for Parkinson's disease].

    PubMed

    Gajo, Gianandrea; Pollak, Pierre; Lüscher, Christian; Benninger, David

    2015-04-29

    Parkinson's disease (PD) is a major socio-economic burden increasing with the aging population. In advanced PD, the emergence of symptoms refractory to conventional therapy poses a therapeutic challenge. The success of deep brain stimulation (DBS) and advances in the understanding of the pathophysiology of PD have raised interest in non-invasive brain stimulation (NIBS) as an alternative therapeutic tool. NIBS could offer an alternative approach for patients at risk who are excluded from surgery and/or to treat refractory symptoms. The treatment of the freezing of gait, a major cause of disability and falls in PD patients, could be enhanced by transcranial direct current stimulation (tDCS). A therapeutic study is currently performed at the Department of Neurology at the CHUV.

  8. Physician liability and non-invasive prenatal testing.

    PubMed

    Toews, Maeghan; Caulfield, Timothy

    2014-10-01

    Although non-invasive prenatal testing (NIPT) marks a notable development in the field of prenatal genetic testing, there are some physician liability considerations raised by this technology. As NIPT is still emerging as the standard of care and is just starting to receive provincial funding, the question arises of whether physicians are obligated to disclose the availability of NIPT to eligible patients as part of the physician-patient discussion about prenatal screening and diagnosis. If NIPT is discussed with patients, it is important to disclose the limitations of this technology with respect to its accuracy and the number of disorders that it can detect when compared with invasive diagnostic options. A failure to sufficiently disclose these limitations could leave patients with false assurances about the health of their fetuses and could raise informed consent and liability issues, particularly if a child is born with a disability as a result.

  9. Non-Invasive Brain Stimulation in Neglect Rehabilitation: An Update

    PubMed Central

    Müri, René Martin; Cazzoli, Dario; Nef, Tobias; Mosimann, Urs P.; Hopfner, Simone; Nyffeler, Thomas

    2013-01-01

    Here, we review the effects of non-invasive brain stimulation such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies) fulfilling our search criteria. Activity of daily living measures such as the Barthel Index or, more specifically for neglect, the Catherine Bergego Scale were the outcome measure in three studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence. The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta-burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients. PMID:23772209

  10. Non-invasive pressure measuring device and method

    NASA Astrophysics Data System (ADS)

    Welch, Jeanne A.

    1990-12-01

    The invention relates generally to measuring devices and to devices for measuring the pressure in a sealed container. More particularly, the invention relates to a non-invasive device and method for measuring the pressure of a gas in a double-envelope lamp. An infrared gaseous discharge lamp of integrated double-envelope construction has an inner chamber or envelope filled with a gaseous medium under relatively high pressure which provides illumination when the lamp is energized. The outer chamber or envelope is normally evacuated or otherwise provided with a relatively low-pressure gas. Double-envelope lamps are subject to gas leaks from the inner chamber to the outer chamber. Eventually, these leaks may lead to catastrophic lamp failure by a mechanism that involves electric arcing in the outer chamber.

  11. Non-invasive prenatal testing: ethics and policy considerations.

    PubMed

    Vanstone, Meredith; King, Carol; de Vrijer, Barbra; Nisker, Jeff

    2014-06-01

    New technologies analyzing fetal DNA in maternal blood have led to the wide commercial availability of non-invasive prenatal testing (NIPT). We present here for clinicians the ethical and policy issues related to an emerging practice option. Although NIPT presents opportunities for pregnant women, particularly women who are at increased risk of having a baby with an abnormality or who are otherwise likely to access invasive prenatal testing, NIPT brings significant ethics and policy challenges. The ethical issues include multiple aspects of informed decision-making, such as access to counselling about the possible results of the test in advance of making a decision about participation in NIPT. Policy considerations include issues related to offering and promoting a privately available medical strategy in publicly funded institutions. Ethics and policy considerations merge in NIPT with regard to sex selection and support for persons living with disabilities.

  12. Moral Enhancement Using Non-invasive Brain Stimulation.

    PubMed

    Darby, R Ryan; Pascual-Leone, Alvaro

    2017-01-01

    Biomedical enhancement refers to the use of biomedical interventions to improve capacities beyond normal, rather than to treat deficiencies due to diseases. Enhancement can target physical or cognitive capacities, but also complex human behaviors such as morality. However, the complexity of normal moral behavior makes it unlikely that morality is a single capacity that can be deficient or enhanced. Instead, our central hypothesis will be that moral behavior results from multiple, interacting cognitive-affective networks in the brain. First, we will test this hypothesis by reviewing evidence for modulation of moral behavior using non-invasive brain stimulation. Next, we will discuss how this evidence affects ethical issues related to the use of moral enhancement. We end with the conclusion that while brain stimulation has the potential to alter moral behavior, such alteration is unlikely to improve moral behavior in all situations, and may even lead to less morally desirable behavior in some instances.

  13. [Non-invasive prenatal testing: challenges for future implementation].

    PubMed

    Henneman, Lidewij; Page-Chrisiaens, G C M L Lieve; Oepkes, Dick

    2015-01-01

    The non-invasive prenatal test (NIPT) is an accurate and safe test in which blood from the pregnant woman is used to investigate if the unborn child possibly has trisomy 21 (Down's syndrome), trisomy 18 (Edwards' syndrome) or trisomy 13 (Patau syndrome). Since April 2014 the NIPT has been available in the Netherlands as part of the TRIDENT implementation project for those in whom the first trimester combined test showed an elevated risk (> 1:200) of trisomy, or on medical indication, as an alternative to chorionic villous sampling or amniocentesis. Since the introduction of the NIPT the use of these invasive tests, which are associated with a risk of miscarriage, has fallen steeply. The NIPT may replace the combined test. Also the number of conditions that is tested for can be increased. Modification of current prenatal screening will require extensive discussion, but whatever the modification, careful counseling remains essential to facilitate pregnant women's autonomous reproductive decision making.

  14. Novel non invasive diagnostic strategies in bladder cancer

    PubMed Central

    TRUTA, ANAMARIA; POPON, TUDOR ADRIAN HODOR; SARACI, GEORGE; GHERVAN, LIVIU; POP, IOAN VICTOR

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, −145, −222, −210, −10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population. PMID:27152066

  15. Novel non invasive diagnostic strategies in bladder cancer.

    PubMed

    Truta, Anamaria; Popon, Tudor Adrian Hodor; Saraci, George; Ghervan, Liviu; Pop, Ioan Victor

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, -145, -222, -210, -10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population.

  16. Confocal raman microscopy as a non-invasive tool to investigate the phase composition of frozen complex cryopreservation media.

    PubMed

    Kreiner-Møller, A; Stracke, F; Zimmermann, H

    2013-01-01

    Various cryoprotective agents (CPA) are added to cell media in order to avoid cell injury during cryo preservation. The resulting complex environment of the preserved cell, consisting of crystalline and liquid phases can however not be investigated non-invasively by established methods in cryobiology. This study shows how scanning confocal Raman microscopy can non-invasively extract information on chemical composition, phase domain and distribution at cryogenic temperatures. The formation of the salt hydrate, hydrohalite NaCl∙H2O, in solutions comprised of phosphate buffered saline (PBS) and dimethyl sulphoxide (DMSO) is studied in particular. Scanning confocal Raman microscopy can be used to unambiguously identify hydrohalite in a medium containing DMSO and saline. The confocal Raman microscopy imaging along with differential scanning calorimetric measurements further show that the hydrohalite is formed without eutectic formation. This method also allows for discrimination between closely packed hydrohalite crystals that are oriented differently.

  17. Silica-coated bismuth sulfide nanorods as multimodal contrast agents for a non-invasive visualization of the gastrointestinal tract

    NASA Astrophysics Data System (ADS)

    Zheng, Xiaopeng; Shi, Junxin; Bu, Yang; Tian, Gan; Zhang, Xiao; Yin, Wenyan; Gao, Bifen; Yang, Zhiyong; Hu, Zhongbo; Liu, Xiangfeng; Yan, Liang; Gu, Zhanjun; Zhao, Yuliang

    2015-07-01

    Non-invasive and real-time imaging of the gastrointestinal (GI) tract is particularly desirable for research and clinical studies of patients with symptoms arising from gastrointestinal diseases. Here, we designed and fabricated silica-coated bismuth sulfide nanorods (Bi2S3@SiO2 NRs) for a non-invasive spatial-temporally imaging of the GI tract. The Bi2S3 NRs were synthesized by a facile solvothermal method and then coated with a SiO2 layer to improve their biocompatibility and stability in the harsh environments of the GI tract, such as the stomach and the small intestine. Due to their strong X-ray- and near infrared-absorption abilities, we demonstrate that, following oral administration in mice, the Bi2S3@SiO2 NRs can be used as a dual-modal contrast agent for the real-time and non-invasive visualization of NRs distribution and the GI tract via both X-ray computed tomography (CT) and photoacoustic tomography (PAT) techniques. Importantly, integration of PAT with CT provides complementary information on anatomical details with high spatial resolution. In addition, we use Caenorhabditis Elegans (C. Elegans) as a simple model organism to investigate the biological response of Bi2S3@SiO2 NRs by oral administration. The results indicate that these NRs can pass through the GI tract of C. Elegans without inducing notable toxicological effects. The above results suggest that Bi2S3@SiO2 NRs pave an alternative way for the fabrication of multi-modal contrast agents which integrate CT and PAT modalities for a direct and non-invasive visualization of the GI tract with low toxicity.Non-invasive and real-time imaging of the gastrointestinal (GI) tract is particularly desirable for research and clinical studies of patients with symptoms arising from gastrointestinal diseases. Here, we designed and fabricated silica-coated bismuth sulfide nanorods (Bi2S3@SiO2 NRs) for a non-invasive spatial-temporally imaging of the GI tract. The Bi2S3 NRs were synthesized by a facile

  18. Non-invasive characterization of structure and morphology of silk fibroin biomaterials using non-linear microscopy

    PubMed Central

    Rice, William L.; Firdous, Shamaraz; Gupta, Sharad; Hunter, Martin; Foo, Cheryl Wong Po; Wang, Yongzhong; Kim, Hyeon Joo; Kaplan, David L.; Georgakoudi, Irene

    2009-01-01

    Designing biomaterial scaffolds remains a major challenge in tissue engineering. Key to this challenge is improved understanding of the relationships between the scaffold properties and its degradation kinetics, as well as the cell interactions and the promotion of new matrix deposition. Here we present the use of non-linear spectroscopic imaging as a non-invasive method to characterize not only morphological, but also structural aspects of silkworm silk fibroin-based biomaterials, relying entirely on endogenous optical contrast. We demonstrate that two photon excited fluorescence and second harmonic generation are sensitive to the hydration, overall β sheet content and molecular orientation of the sample. Thus, the functional content and high resolution afforded by these non-invasive approaches offer promise for identifying important connections between biomaterial design and functional engineered tissue development. The strategies described also have broader implications for understanding and tracking the remodeling of degradable biomaterials under dynamic conditions both in vitro and in vivo. PMID:18291520

  19. Use of perfluorocarbon nanoparticles for non-invasive multimodal cell tracking of human pancreatic islets

    PubMed Central

    Barnett, Brad P.; Ruiz-Cabello, Jesus; Hota, Partha; Ouwerkerk, Ronald; Shamblott, Michael J.; Lauzon, Cal; Walczak, Piotr; Gilson, Wesley D.; Chacko, Vadappuram P.; Kraitchman, Dara L.; Arepally, Aravind; Bulte, Jeff W. M.

    2011-01-01

    In vivo imaging of engraftment and immunorejection of transplanted islets is critical for further clinical development, with 1H MR imaging of superparamagnetic iron oxide-labeled cells being the current premier modality. Using perfluorocarbon nanoparticles, we present here a strategy for non-invasive imaging of cells using other modalities. To this end, human cadaveric islets were labeled with rhodamine-perfluorooctylbromide (PFOB) nanoparticles, rhodamine-perfluoropolyether (PFPE) nanoparticles or Feridex® as control and tested in vitro for cell viability and c-peptide secretion for 1 week. 19F MRI, computed tomography (CT) and ultrasound (US) imaging was performed on labeled cell phantoms and on cells following transplantation beneath the kidney capsule of mice and rabbits. PFOB and PFPE-labeling did not reduce human islet viability or glucose responsiveness as compared with unlabeled cells or SPIO-labeled cells. PFOB- and PFPE-labeled islets were effectively fluorinated for visualization by 19F MRI. PFOB-labeled islets were acoustically reflective for detection by US imaging and became sufficiently brominated to become radiopaque allowing visualization with CT. Thus, perfluorocarbon nanoparticles are multimodal cellular contrast agents that may find applications in real-time targeted delivery and imaging of transplanted human islets or other cells in a clinically applicable manner using MRI, US or CT imaging. PMID:21861285

  20. Use of perfluorocarbon nanoparticles for non-invasive multimodal cell tracking of human pancreatic islets.

    PubMed

    Barnett, Brad P; Ruiz-Cabello, Jesus; Hota, Partha; Ouwerkerk, Ronald; Shamblott, Michael J; Lauzon, Cal; Walczak, Piotr; Gilson, Wesley D; Chacko, Vadappuram P; Kraitchman, Dara L; Arepally, Aravind; Bulte, Jeff W M

    2011-01-01

    In vivo imaging of engraftment and immunorejection of transplanted islets is critical for further clinical development, with (1)H MR imaging of superparamagnetic iron oxide-labeled cells being the current premier modality. Using perfluorocarbon nanoparticles, we present here a strategy for non-invasive imaging of cells using other modalities. To this end, human cadaveric islets were labeled with rhodamine-perfluorooctylbromide (PFOB) nanoparticles, rhodamine-perfluoropolyether (PFPE) nanoparticles or Feridex as control and tested in vitro for cell viability and c-peptide secretion for 1 week. (19)F MRI, computed tomography (CT) and ultrasound (US) imaging was performed on labeled cell phantoms and on cells following transplantation beneath the kidney capsule of mice and rabbits. PFOB and PFPE-labeling did not reduce human islet viability or glucose responsiveness as compared with unlabeled cells or SPIO-labeled cells. PFOB- and PFPE-labeled islets were effectively fluorinated for visualization by (19)F MRI. PFOB-labeled islets were acoustically reflective for detection by US imaging and became sufficiently brominated to become radiopaque allowing visualization with CT. Thus, perfluorocarbon nanoparticles are multimodal cellular contrast agents that may find applications in real-time targeted delivery and imaging of transplanted human islets or other cells in a clinically applicable manner using MRI, US or CT imaging.

  1. Raman Spectrometric Detection Methods for Early and Non-Invasive Diagnosis of Alzheimer's Disease.

    PubMed

    Huang, Chia-Chi; Isidoro, Ciro

    2017-03-18

    The continuous increasing rate of patients suffering of Alzheimer's disease (AD) worldwide requires the adoption of novel techniques for non-invasive early diagnosis and monitoring of the disease. Here we review the various Raman spectroscopic techniques, including Fourier Transform-Raman spectroscopy, surface-enhanced Raman scattering spectroscopy, coherent anti-Stokes Raman scattering spectroscopy, and confocal Raman microspectroscopy, that could be used for the diagnosis of AD. These techniques have shown the potential to detect AD biomarkers, such as the amyloid-β peptide and the tau protein, or the neurotransmitters involved in the disease (e.g., Glutamate and γ-Aminobutyric acid), or the typical structural alterations in specific brain areas. The possibility to detect the specific biomarkers in liquid biopsies and to obtain high resolution 3D microscope images of the affected area make the Raman spectroscopy a valuable ally in the early diagnosis and monitoring of AD.

  2. Two Non-Invasive Optical Diagnostics for the Plasma Couette Experiment

    NASA Astrophysics Data System (ADS)

    Tabbutt, Megan; Flanagan, Ken; Milhone, Jason; Nornberg, Mark; Roesler, Fred; Forest, Cary; WiPAL Team Team

    2016-10-01

    Two non-invasive optical diagnostics have been developed for the Plasma Couette Experiment Upgrade (PCX-U). PCX-U is capable of producing electron temperatures of 5 to 15 eV, densities between 1010 and 5 ×1011 cm-3, and ion temperatures between 0.5 eV to 2 eV. The first diagnostic described utilizes a low cost USB spectrometer for optical emission spectroscopy (OES). Combined with a modified coronal model, OES is used to measure electron temperature in Argon plasmas. A higher resolution spectrometer is used to image ion lines which can be analyzed to determine moments of the ion energy distribution function, particularly ion temperature and flow. Both optical diagnostics are mounted on a linear stage for scanning chords across the plasma volume. Abel transform techniques are used to create radial profiles of measured plasma properties. DOE, NSF.

  3. Neurosonological Examination: A Non-Invasive Approach for the Detection of Cerebrovascular Impairment in AD

    PubMed Central

    Urbanova, Barbora; Tomek, Ales; Mikulik, Robert; Magerova, Hana; Horinek, Daniel; Hort, Jakub

    2014-01-01

    There has been a growing interest in vascular impairment associated with Alzheimer’s disease (AD). This interest was stimulated by the findings of higher incidence of vascular risk factors in AD. Signs of vascular impairment were investigated notably in the field of imaging methods. Our aim was to explore ultrasonographic studies of extra- and intracranial vessels in patients with AD and mild cognitive impairment (MCI) and define implications for diagnosis, treatment, and prevention of the disease. The most frequently studied parameters with extracranial ultrasound are intima-media thickness in common carotid artery, carotid atherosclerosis, and total cerebral blood flow. The transcranial ultrasound concentrates mostly on flow velocities, pulsatility indices, cerebrovascular reserve capacity, and cerebral microembolization. Studies suggest that there is morphological and functional impairment of cerebral circulation in AD compared to healthy subjects. Ultrasound as a non-invasive method could be potentially useful in identifying individuals in a higher risk of progression of cognitive decline. PMID:24478651

  4. Non-invasive sex assessment in bovine semen by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    De Luca, A. C.; Managó, S.; Ferrara, M. A.; Rendina, I.; Sirleto, L.; Puglisi, R.; Balduzzi, D.; Galli, A.; Ferraro, P.; Coppola, G.

    2014-05-01

    X- and Y-chromosome-bearing sperm cell sorting is of great interest, especially for animal production management systems and genetic improvement programs. Here, we demonstrate an optical method based on Raman spectroscopy to separate X- and Y-chromosome-bearing sperm cells, overcoming many of the limitations associated with current sex-sorting protocols. A priori Raman imaging of bull spermatozoa was utilized to select the sampling points (head-neck region), which were then used to discriminate cells based on a spectral classification model. Main variations of Raman peaks associated with the DNA content were observed together with a variation due to the sex membrane proteins. Next, we used principal component analysis to determine the efficiency of our device as a cell sorting method. The results (>90% accuracy) demonstrated that Raman spectroscopy is a powerful candidate for the development of a highly efficient, non-invasive, and non-destructive tool for sperm sexing.

  5. A Non-invasive 24 Hours Stabilization of Duodenal Ulcer Perforation by a Combination Regimen

    PubMed Central

    Zil-E-Ali, Ahsan; Bin Shafique, Muhammad; Ali, Hammad; Ghani, Usman

    2016-01-01

    Surgical repair of perforated gastroduodenal ulcer has been extensively practiced in emergency clinical situations. Non-invasive conservation treatment is regaining the attention towards management of such ulcers. We report the case of a 50-year-old male smoker who presented in the emergency unit with acute generalized abdominal pain and guarding in the epigastric and right upper quadrant region. He is a known regular user of over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDS) for more than 10 years for his osteoarthiritis and myalgias. A differential diagnosis of gastritis and duodenal perforation was made owing to the symptoms and long usage of NSAIDs. He was managed with an intravenous proton pump inhibitor and intravenous antibiotics. This therapy lead to stabilization of the clinical symptoms as well as laboratory and imaging studies. PMID:28083452

  6. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, Michael P.

    1996-01-01

    A coaxial hyperthermia applicator for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator.

  7. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, M.P.

    1996-08-27

    A coaxial hyperthermia applicator is disclosed for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator. 11 figs.

  8. Tissue Damage Characterization Using Non-invasive Optical Modalities

    NASA Astrophysics Data System (ADS)

    Diaz, David

    The ability to determine the degree of cutaneous and subcutaneous tissue damage is essential for proper wound assessment and a significant factor for determining patient treatment and morbidity. Accurate characterization of tissue damage is critical for a number of medical applications including surgical removal of nonviable tissue, severity assessment of subcutaneous ulcers, and depth assessment of visually open wounds. The main objective of this research was to develop a non-invasive method for identifying the extent of tissue damage underneath intact skin that is not apparent upon visual examination. This work investigated the relationship between tissue optical properties, blood flow, and tissue viability by testing the hypotheses that (a) changes in tissue oxygenation and/or microcirculatory blood flow measurable by Diffuse Near Infrared Spectroscopy (DNIRS) and Diffuse Correlation Spectroscopy (DCS) differ between healthy and damaged tissue and (b) the magnitude of those changes differs for different degrees of tissue damage. This was accomplished by developing and validating a procedure for measuring microcirculatory blood flow and tissue oxygenation dynamics at multiple depths (up to 1 centimeter) using non-invasive DCS and DNIRS technologies. Due to the lack of pressure ulcer animal models that are compatible with our optical systems, a proof of concept was conducted in a porcine burn model prior to conducting clinical trials in order to assess the efficacy of the system in-vivo. A reduction in total hemoglobin was observed for superficial (5%) and deep burns (35%) along with a statistically significant difference between the optical properties of superficial and deep burns (p < 0.05). Burn depth and viable vessel density were estimated via histological samples. 42% of vessels in the dermal layer were viable for superficial burns, compared to 25% for deep burns. The differences detected in optical properties and hemoglobin content by optical measurements

  9. Lung tumor tracking in fluoroscopic video based on optical flow.

    PubMed

    Xu, Qianyi; Hamilton, Russell J; Schowengerdt, Robert A; Alexander, Brian; Jiang, Steve B

    2008-12-01

    Respiratory gating and tumor tracking for dynamic multileaf collimator delivery require accurate and real-time localization of the lung tumor position during treatment. Deriving tumor position from external surrogates such as abdominal surface motion may have large uncertainties due to the intra- and interfraction variations of the correlation between the external surrogates and internal tumor motion. Implanted fiducial markers can be used to track tumors fluoroscopically in real time with sufficient accuracy. However, it may not be a practical procedure when implanting fiducials bronchoscopically. In this work, a method is presented to track the lung tumor mass or relevant anatomic features projected in fluoroscopic images without implanted fiducial markers based on an optical flow algorithm. The algorithm generates the centroid position of the tracked target and ignores shape changes of the tumor mass shadow. The tracking starts with a segmented tumor projection in an initial image frame. Then, the optical flow between this and all incoming frames acquired during treatment delivery is computed as initial estimations of tumor centroid displacements. The tumor contour in the initial frame is transferred to the incoming frames based on the average of the motion vectors, and its positions in the incoming frames are determined by fine-tuning the contour positions using a template matching algorithm with a small search range. The tracking results were validated by comparing with clinician determined contours on each frame. The position difference in 95% of the frames was found to be less than 1.4 pixels (approximately 0.7 mm) in the best case and 2.8 pixels (approximately 1.4 mm) in the worst case for the five patients studied.

  10. Applied potential tomography: a new non-invasive technique for assessing gastric function.

    PubMed

    Mangnall, Y F; Baxter, A J; Avill, R; Bird, N C; Brown, B H; Barber, D C; Seagar, A D; Johnson, A G; Read, N W

    1987-01-01

    Applied potential tomography is a new, non-invasive technique that yields sequential images of the resistivity of gastric contents after subjects have ingested a liquid or semi-solid meal. This study validates the technique as a means of measuring gastric emptying. Experiments in vitro showed an excellent correlation between measurements of resistivity and either the square of the radius of a glass rod or the volume of water in a spherical balloon when both were placed in an oval tank containing saline. Altering the lateral position of the rod in the tank did not alter the values obtained. Images of abdominal resistivity were also directly correlated with the volume of air in a gastric balloon. Profiles of gastric emptying of liquid meals obtained using APT were very similar to those obtained using scintigraphy or dye dilution techniques provided that acid secretion was inhibited by cimetidine. Profiles of emptying of a mashed potato meal using APT were also very similar to those obtained by scintigraphy. Measurements of the emptying of a liquid meal from the stomach were reproducible if acid secretion was inhibited by cimetidine. Thus, APT is an accurate and reproducible method of measuring gastric emptying of liquids and particulate food. It is inexpensive, well tolerated, easy to use and ideally suited for multiple studies in patients, even those who are pregnant. A preliminary study is also presented that assesses the technique as a means of measuring gastric acid secretion. Comparison of resistivity changes with measured acid secretion following the injection of pentagastrin shows good correlations. APT might offer a non-invasive alternative to the use of a nasogastric tube and acid collection.

  11. Non-invasive shallow seismic source comparison for hazardous waste site investigations

    SciTech Connect

    Doll, W.E.; Miller, R.D.; Xia, J.

    1994-12-31

    Many commonly used shallow seismic sources are unacceptable for hazardous waste site investigations because they risk exhumation of contaminants in the soil, they add contaminants (e.g. lead) which are not allowed by regulations, or they add new migration paths for contaminants. Furthermore, recently developed high frequency vibrators for shallow investigations could be more effective at some sites than non-invasive impulsive sources because of their ability to tailor the source spectrum and reduce interference. The authors show preliminary results of a comparison test of eight non-invasive impulsive and swept sources in preparation for seismic reflection profiling on the Oak Ridge Reservation, Tennessee. Well log data are used to determine geologic contacts and to generate synthetic seismograms for the site. Common midpoint (CMP) seismic data for each source were collected at 95 geophone groups from 125 shot points along a 400m test line. Hydrophone data were obtained at 1.5m spacing between 61m and 133m depth in a hole near the center of the CMP line. As of March, 1994, brute stacks have been completed for three of the eight sources. Depth penetration is demonstrated in brute stacks and shot gathers, which show a 200ms reflector for all of the sources tested along portions of the line. Source effectiveness will also be evaluated by comparing images of several shallower reflectors (40--150ms) which are apparent in many of the records. Imaging of these reflectors appears to depend upon the ability of the source to generate sufficient high frequency energy (>100 Hz).

  12. Non-invasive Technology to Study Local Passivity Breakdown of Metal Alloys in Aqueous Media

    SciTech Connect

    Alan M. Shipley

    2005-03-09

    Little is known about the basic mechanisms of passive oxide breakdown, repair, and localized corrosion of metals. A non-invasive instrument and methods have been developed to study local events and mechanisms that initiate passivity breakdown and subsequent corrosion of metals in aqueous media. The ''difference viewer imaging technique'' (DVIT) is a rapid, real time, non-invasive assay to study metal surfaces in corrosive solutions. It has a spatial resolution of less than 10.0 ?m (1cm x 1cm sample, 1000 x 1000 pixel CCD) to observe initial corrosion processes of the order of seconds. DVIT is a software-controlled video microscopy system and methods to collect and analyze pixel changes in video images. These images are recorded from a digital CCD video camera and frame grabber package using visible light for illumination. The DVIT system detects changes in video images that represent initial corrosive events that lead to passivity breakdown and re-passivation on metal surfaces in situ. This visual technique is easy to use and apply. It compliments other metal surface measurement techniques and can be used simultaneously with them. DVIT has proven to be more sensitive in detecting changes than scanning microelectrode techniques. DVIT is also much easier than other methods to apply and operate. It has the further advantage of providing a real time image of the entire metal surface under study instead of waiting for a microelectrode to scan a number of data points over a sample then plot the results. This project has fulfilled all specifications as outlined in the Department of Energy solicitation responsible for this grant application and award and exceeded a number of the specifications. Applicable Electronics, Inc. now has a marketable instrument and software package available for sale now. Further development of the system will be ongoing as driven by customer needs and discoveries. This technology has immediate applications in corrosion labs to further study

  13. Fluoroscopic performance tests using a portable computer/frame grabber: Wiener spectra measurements.

    PubMed

    Goldman, L W

    1992-01-01

    Currently, routine tests of fluoroscopic image quality in common use are highly subjective. As part of an effort to develop more quantitative routine tests of fluoroscopic image quality, a method was developed to quickly and easily measure Wiener spectra (WS) of TV-viewed fluoroscopic systems that considers both spatial and temporal noise correlations. A PC-mounted frame grabber captures images at the TV frame rate to form a three-dimensional (3-D) array of pixels. Scans of a "two-dimensional slit" are then synthesized from which a one-dimensional central section of a 3-D WS is calculated. To avoid errors due to coarse (8-bit) quantization, a video amplifier is used to expand a portion of the signal to the full digitizer range. A reference signal (2 mm of aluminum) is then used to normalize image contrast. Ensemble averages of 250 spectra were obtained in approximately 1 min, including all processing. Results are presented to demonstrate reproducibility, sensitivity, and behavior of the WS. The eventual goal of this work is to use this method in conjunction with measurements of an MTF to calculate fundamental descriptors of image quality, such as SNR and NEQ.

  14. Accuracy of Percutaneous Lumbosacral Pedicle Screw Placement Using the Oblique Fluoroscopic View Based on Computed Tomography Evaluations

    PubMed Central

    Sato, Koji; Kanemura, Tokumi; Iwase, Toshiki; Togawa, Daisuke; Matsuyama, Yukihiro

    2016-01-01

    Study Design Retrospective. Purpose This study aims to investigate the accuracy of the oblique fluoroscopic view, based on preoperative computed tomography (CT) images for accurate placement of lumbosacral percutaneous pedicle screws (PPS). Overview of Literature Although PPS misplacement has been reported as one of the main complications in minimally invasive spine surgery, there is no comparative data on the misplacement rate among different fluoroscopic techniques, or comparing such techniques with open procedures. Methods We retrospectively selected 230 consecutive patients who underwent posterior spinal fusion with a pedicle screw construct for degenerative lumbar disease, and divided them into 3 groups, those who had undergone: minimally invasive percutaneous procedure using biplane (lateral and anterior-posterior views using a single C-arm) fluoroscope views (group M-1), minimally invasive percutaneous procedure using the oblique fluoroscopic view based on preoperative CT (group M-2), and conventional open procedure using a lateral fluoroscopic view (group O: controls). The relative position of the screw to the pedicle was graded for the pedicle breach as no breach, <2 mm, 2–4 mm, or >4 mm. Inaccuracy was calculated and assessed according to the spinal level, direction and neurological deficit. Inter-group radiation exposure was estimated using fluoroscopy time. Results Inaccuracy involved an incline toward L5, causing medial or lateral perforation of pedicles in group M-1, but it was distributed relatively equally throughout multiple levels in groups M-2 and controls. The mean fluoroscopy time/case ranged from 1.6 to 3.9 minutes. Conclusions Minimally invasive lumbosacral PPS placement using the conventional fluoroscopic technique carries an increased risk of inaccurate screw placement and resultant neurological deficits, compared with that of the open procedure. Inaccuracy tended to be distributed between medial and lateral perforations of the L5 pedicle

  15. Transcriptome Analysis Showed a Differential Signature between Invasive and Non-invasive Corticotrophinomas

    PubMed Central

    de Araújo, Leonardo Jose Tadeu; Lerario, Antonio Marcondes; de Castro, Margaret; Martins, Clarissa Silva; Bronstein, Marcello Delano; Machado, Marcio Carlos; Trarbach, Ericka Barbosa; Villares Fragoso, Maria Candida Barisson

    2017-01-01

    ACTH-dependent hypercortisolism caused by a pituitary adenoma [Cushing’s disease (CD)] is the most common cause of endogenous Cushing’s syndrome. CD is often associated with several morbidities, including hypertension, diabetes, osteoporosis/bone fractures, secondary infections, and increased cardiovascular mortality. While the majority (≈80%) of the corticotrophinomas visible on pituitary magnetic resonance imaging are microadenomas (MICs, <10 mm of diameter), some tumors are macroadenomas (MACs, ≥10 mm) with increased growth potential and invasiveness, exceptionally exhibiting malignant demeanor. In addition, larger and invasive MACs are associated with a significant increased risk of local complications, such as hypopituitarism and visual defects. Given the clinical and molecular heterogeneity of corticotrophinomas, the aim of this study was to investigate the pattern of genetic differential expression between MIC and MAC, including the invasiveness grade as a criterion for categorizing these tumors. In this study, were included tumor samples from patients with clinical, laboratorial, radiological, and histopathological diagnosis of hypercortisolism due to an ACTH-producing pituitary adenoma. Differential gene expression was studied using an Affymetrix microarray platform in 12 corticotrophinomas, classified as non-invasive MIC (n = 4) and MAC (n = 5), and invasive MAC (n = 3), according to modified Hardy criteria. Somatic mutations in USP8 were also investigated, but none of the patients exhibited USP8 variants. Differential expression analysis demonstrated that non-invasive MIC and MAC have a similar genetic signature, while invasive MACs exhibited a differential expression profile. Among the genes differentially expressed, we highlighted CCND2, ZNF676, DAPK1, and TIMP2, and their differential expression was validated through quantitative real-time PCR in another cohort of 15 non-invasive and 3 invasive cortocotrophinomas. We also

  16. Non-invasive administration of biodegradable nano-carrier vaccines

    PubMed Central

    Kalam, Mohd Abul; Khan, Abdul Arif; Alshamsan, Aws

    2017-01-01

    Polymeric nanoparticulate carriers play an important role and holding a significant potential for the development of novel immunomodulatory agents as easily they are taken up by antigen presenting cells. They allow an enhanced antigen stability, better immunogenicity and immunostimulatory effect with sustained and controlled release of the antigen to the target sites. Better information and vital understanding of mechanism of action, interaction of such vectors with the APCs and dendritic cells and antigen release kinetics in immunomodulatory effects, and improved knowledge of their in vivo fate and distribution are now needed, those collectively would speed up the rational strategies of nanoparticles as carriers for vaccines and other protein antigens. The evolution of such innovative adjuvants for protein and DNA immunizations are an exciting and growing zone in immunology, which may enhance the clinical outcomes in many infectious and non-infectious diseases. This review summarizes the recent advances in nano-vaccinology with polymeric (especially biodegradable) carriers, their methods of preparation, surface modification, their interaction with antigen presenting cells, release of antigens, its kinetics and mechanism in the delivery of vaccines via non-invasive routes. PMID:28123631

  17. Non-invasive ventilation in amyotrophic lateral sclerosis.

    PubMed

    Vrijsen, Bart; Testelmans, Dries; Belge, Catharina; Robberecht, Wim; Van Damme, Philip; Buyse, Bertien

    2013-03-01

    Abstract Non-invasive ventilation (NIV) is widely used to improve alveolar hypoventilation in amyotrophic lateral sclerosis. Several studies indicate a better survival when NIV is used, certainly in patients with none to moderate bulbar dysfunction. Data on quality of life (QoL) are rather disputable. Overall QoL is shown to be equivalent in patients with or without NIV, although health-related QoL is shown to be increased in patients with none to moderate bulbar dysfunction. NIV improves sleep quality, although patient-ventilator asynchronies are demonstrated. FVC < 50%, seated or supine, has been widely applied as threshold to initiate NIV. Today, measurements of respiratory muscle strength, nocturnal gas exchange and symptomatic complaints are used as indicators to start NIV. Being compliant with NIV therapy increases QoL and survival. Cough augmentation has an important role in appropriate NIV. Patients have today more technical options and patients with benefit from these advances are growing in number. Tracheal ventilation needs to be discussed when NIV seems impossible or becomes insufficient.

  18. Mucositis and non-invasive markers of small intestinal function.

    PubMed

    Tooley, Katie L; Howarth, Gordon S; Butler, Ross N

    2009-05-01

    Mucositis is a common and debilitating side effect of chemotherapy that manifests due to the inability of chemotherapy agents to discriminate between normal and neoplastic cells. This results in ulcerating lesions lining the gastrointestinal tract. Moreover, the development of efficacious treatments for small intestinal mucositis has been hindered as the pathobiology of mucositis is still not fully understood. The small intestine is an extensive organ which is largely inaccessible by conventional means. Non-invasive biomarkers such as small intestinal permeability, H(2) breath tests, serum citrulline tests and the (13)C-sucrose breath test (SBT) have emerged as potential markers of small intestinal function. The SBT is emerging as the more appropriate biomarker to assess chemotherapy-induced mucositis in cancer patients and animal models, where it measures the decrease in sucrase activity associated with villus blunting and crypt disruption. The SBT has been successfully applied to detect mucositis induced by different classes of chemotherapy agents and has been used successfully to monitor small intestinal function with a range of candidate anti-mucositis treatments. We propose the SBT a superior biomarker of small intestinal function that could be successfully applied in clinical practice for monitoring the development of mucositis in cancer patients undergoing chemotherapy.

  19. Alteration of Political Belief by Non-invasive Brain Stimulation.

    PubMed

    Chawke, Caroline; Kanai, Ryota

    2015-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to.

  20. Non-invasive diagnosis of mitral regurgitation by Doppler echocardiography.

    PubMed Central

    Blanchard, D; Diebold, B; Peronneau, P; Foult, J M; Nee, M; Guermonprez, J L; Maurice, P

    1981-01-01

    The value of Doppler echocardiography for the non-invasive diagnosis of mitral regurgitation was studied blindly in 161 consecutive invasively investigated adult patients. Regurgitation was graded from 0 to 3 at selective left ventricular angiography. The Doppler echocardiographic examination was considered to be positive when a disturbed systolic flow was found within the left atrium behind the aorta or the anterior leaflet of the mitral valve. The test was considered to be negative in the absence of a regurgitant jet. The level of the signal to noise ratio was checked by the recording of the ventricular filling flow. The study was performed in 131 cases from the left side of the sternum and in 101 cases from the apex. There were no false positives and thus the specificity was 100 per cent. The 20 false negatives were all in patients with grade 1 regurgitation. Thus only some (33%) instances of mild regurgitation were misdiagnosed, and the sensitivity for moderate to severe mitral regurgitation was 100 per cent. PMID:7236465

  1. Non-invasive biosensor and wilreless interrogating system for hypoglycemia

    NASA Astrophysics Data System (ADS)

    Varadan, Vijay K.; Whitchurch, Ashwin K.; Saukesi, K.

    2002-11-01

    Hypoglycemia - abnormal decrease in blood sugar - is a major obstacle in the management of diabetes and prevention of long-term complications, and it may impose serious effects on the brain, including impairment of memory and other cognitive functions. This paper presents the development of a non-invasive sensor with miniaturized telemetry device in a wrist-watch for monitoring glucose concentration in blood. The sensor concept is based on optical chiralit of glucose level in the interstitial fluid. The wrist watch consists of a laser power source of the wavelength compatible with the glucose. A nanofilm with specific chirality is placed at the bottom of the watch. The light then passes through the film and illuminates a small area on the skin.It has been documented that there is certain concentration of sugar level is taken by the intertitial fluid from the blood stream and deposit a portion of it at the dead skin. The wrist-watch when in contact with the outer skin of the human will thus monitor the glucose concentration. A wireless monitoring system in the watch then downloads the data from the watch to a Palm or laptop computer.

  2. Non-invasive methods in paediatric exercise physiology.

    PubMed

    Armstrong, Neil; Fawkner, Samantha G

    2008-04-01

    Oded Bar-Or's hypothesis that children may be "metabolic non-specialists", even when engaging in specialized sports, has stimulated the study of paediatric exercise metabolism since the publication of his classic text Pediatric sports medicine for the practitioner in 1983. Evidence drawn from several methodologies indicates an interplay of anaerobic and aerobic exercise metabolism in which children have a relatively higher metabolic contribution from oxidative energy pathways than adolescents or adults, whereas there is a progressive increase in glycolytic support of exercise with age, at least into adolescence and possibly into young adulthood. The picture is generally consistent but incomplete, as research with young people has been limited by both ethical and methodological constraints. The recent rigorous introduction of non-invasive techniques such as breath-by-breath respiratory gas analysis and magnetic resonance spectroscopy into paediatric exercise physiology promises to open up new avenues of research and generate unique insights into the metabolism of the exercising muscle during growth and maturation. It therefore appears that we might have available the tools necessary to answer some of the elegant questions raised by Professor Bar-Or over 25 years ago.

  3. Non-Invasive Measurement of Intracranial Pressure Pulsation using Ultrasound

    NASA Technical Reports Server (NTRS)

    Ueno, Toshiaki; Ballard, R. E.; Yost, W. T.; Hargens, A. R.

    1997-01-01

    Exposure to microgravity causes a cephalad fluid shift which may elevate intracranial pressure (ICP). Elevation in ICP may affect cerebral hemodynamics in astronauts during space flight. ICP is, however, a difficult parameter to measure due to the invasiveness of currently available techniques. We already reported our development of a non-invasive ultrasound device for measurement of ICP. We recently modified the device so that we might reproducibly estimate ICP changes in association with cardiac cycles. In the first experiment, we measured changes in cranial distance with the ultrasound device in cadavera while changing ICP by infusing saline into the lateral ventricle. In the second experiment, we measured changes in cranial distance in five healthy volunteers while placing them in 60 deg, 30 deg head-up tilt, supine, and 10 deg head-down tilt position. In the cadaver study, fast Fourier transformation revealed that cranial pulsation is clearly associated with ICP pulsation. The ratio of cranial distance and ICP pulsation is 1.3microns/mmHg. In the tilting study, the magnitudes of cranial pulsation are linearly correlated to tilt angles (r=0.87). The ultrasound device has sufficient sensitivity to detect cranial pulsation in association with cardiac cycles. By analyzing the magnitude of cranial pulsation, estimates of ICP during space flight are possible.

  4. Non-invasive (and minimally invasive) diagnosis of oesophageal varices.

    PubMed

    de Franchis, Roberto

    2008-10-01

    Current guidelines recommend screening all cirrhotic patients by endoscopy, to identify patients at risk of bleeding who should undergo prophylactic treatment. However, since the prevalence of varices in cirrhotic patients is variable, universal screening would imply a large number of unnecessary endoscopies and a heavy burden for endoscopy units. In addition, compliance to screening programs may be hampered by the perceived unpleasantness of endoscopy. Predicting the presence of oesophageal varices by non-invasive means might increase compliance and would permit to restrict the performance of endoscopy to those patients with a high probability of having varices. Over the years, several studies have addressed this issue by assessing the potential of biochemical, clinical and ultrasound parameters, transient elastography, CT scanning and video capsule endoscopy. The platelet count/spleen diameter ratio, CT scanning and video capsule endoscopy have shown promising performance characteristics, although none of them is equivalent to EGD. These methods are perceived by patients as preferable to endoscopy and thus might increase adherence to screening programs. Whether this will compensate for the lower sensitivity of these alternative techniques, and ultimately improve the outcomes if more patients undergo screening, is the crucial question that will have to be answered in the future.

  5. Non-invasive thermometry with multi-frequency microwave radiometry.

    PubMed

    Mizushina, S; Shimizu, T; Sugiura, T

    1992-01-01

    The present status of the development of a non-invasive thermometer based on microwave radiometry at our laboratory is reported. We have developed a model fitting technique combined with a Monte Carlo technique to retrieve temperature-depth profiles from multi (4-6)-frequency-band microwave radiometric data along with confidence intervals (2-sigma) of tissue temperatures as a function of depth. In order to make the radiometric technique compatible with the heating, brightness temperatures are measured through a 1 cm thick water bolus. Results of phantom experiments are presented to demonstrate the above capabilities of the method. Numerical simulation studies have shown that 2-sigma intervals would be 1.0 K or less over a 0-4 cm range and 1.4 K at 5 cm from the surface with using a six-band, 1-5 GHz radiometer having brightness temperature resolution of 0.03 K (3 s integration time). The six-band instrument is currently being assembled at our laboratory.

  6. Public viewpoints on new non-invasive prenatal genetic tests.

    PubMed

    Farrimond, Hannah R; Kelly, Susan E

    2013-08-01

    Prenatal screening programmes have been critiqued for their routine implementation according to clinical rationale without public debate. A new approach, non-invasive prenatal diagnosis (NIPD), promises diagnosis of fetal genetic disorders from a sample of maternal blood without the miscarriage risk of current invasive prenatal tests (e.g. amniocentesis). Little research has investigated the attitudes of wider publics to NIPD. This study used Q-methodology, which combines factor analysis with qualitative comments, to identify four distinct "viewpoints" amongst 71 UK men and women: 1. NIPD as a new tool in the ongoing societal discrimination against the disabled; 2. NIPD as a positive clinical application offering peace of mind in pregnancy; 3. NIPD as a medical option justified for severe disorders only; and 4. NIPD as a valid expansion of personal choice. Concerns included the "trivialisation of testing" and the implications of commercial/direct-to-consumer tests. Q-methodology has considerable potential to identify viewpoints and frame public debate about new technologies.

  7. Reducing proactive aggression through non-invasive brain stimulation.

    PubMed

    Dambacher, Franziska; Schuhmann, Teresa; Lobbestael, Jill; Arntz, Arnoud; Brugman, Suzanne; Sack, Alexander T

    2015-10-01

    Aggressive behavior poses a threat to human collaboration and social safety. It is of utmost importance to identify the functional mechanisms underlying aggression and to develop potential interventions capable of reducing dysfunctional aggressive behavior already at a brain level. We here experimentally shifted fronto-cortical asymmetry to manipulate the underlying motivational emotional states in both male and female participants while assessing the behavioral effects on proactive and reactive aggression. Thirty-two healthy volunteers received either anodal transcranial direct current stimulation to increase neural activity within right dorsolateral prefrontal cortex, or sham stimulation. Aggressive behavior was measured with the Taylor Aggression Paradigm. We revealed a general gender effect, showing that men displayed more behavioral aggression than women. After the induction of right fronto-hemispheric dominance, proactive aggression was reduced in men. This study demonstrates that non-invasive brain stimulation can reduce aggression in men. This is a relevant and promising step to better understand how cortical brain states connect to impulsive actions and to examine the causal role of the prefrontal cortex in aggression. Ultimately, such findings could help to examine whether the brain can be a direct target for potential supportive interventions in clinical settings dealing with overly aggressive patients and/or violent offenders.

  8. Photoionization sensors for non-invasive medical diagnostics

    NASA Astrophysics Data System (ADS)

    Mustafaev, Aleksandr; Rastvorova, Iuliia; Khobnya, Kristina; Podenko, Sofia

    2016-09-01

    The analysis of biomarkers can help to identify the significant number of diseases: lung cancer, tuberculosis, diabetes, high levels of stress, psychosomatic disorders etc. To implement continuous monitoring of the state of human health, compact VUV photoionization detector with current-voltage measurement is designed by Saint-Petersburg Mining University Plasma Research Group. This sensor is based on the patented method of stabilization of electric parameters - CES (Collisional Electron Spectroscopy). During the operation at atmospheric pressure VUV photoionization sensor measures the energy of electrons, produced in the ionization with the resonance photons, whose wavelength situated in the vacuum ultraviolet (VUV). A special software was developed to obtain the second-order derivative of the I-U characteristics, taken by the VUV sensor, to construct the energy spectra of the characteristic electrons. VUV photoionization detector has an unique set of parameters: small size (10*10*1 mm), low cost, wide range of recognizable molecules, as well as accuracy, sufficient for using this instrument for the medical purposes. This device can be used for non-invasive medical diagnostics without compromising the quality of life, for control of environment and human life. Work supported by Foundation for Assistance to Small Innovative Enterprises in Science and Technology.

  9. Uncovering Multisensory Processing through Non-Invasive Brain Stimulation.

    PubMed

    Bolognini, Nadia; Maravita, Angelo

    2011-01-01

    Most of current knowledge about the mechanisms of multisensory integration of environmental stimuli by the human brain derives from neuroimaging experiments. However, neuroimaging studies do not always provide conclusive evidence about the causal role of a given area for multisensory interactions, since these techniques can mainly derive correlations between brain activations and behavior. Conversely, techniques of non-invasive brain stimulation (NIBS) represent a unique and powerful approach to inform models of causal relations between specific brain regions and individual cognitive and perceptual functions. Although NIBS has been widely used in cognitive neuroscience, its use in the study of multisensory processing in the human brain appears a quite novel field of research. In this paper, we review and discuss recent studies that have used two techniques of NIBS, namely transcranial magnetic stimulation and transcranial direct current stimulation, for investigating the causal involvement of unisensory and heteromodal cortical areas in multisensory processing, the effects of multisensory cues on cortical excitability in unisensory areas, and the putative functional connections among different cortical areas subserving multisensory interactions. The emerging view is that NIBS is an essential tool available to neuroscientists seeking for causal relationships between a given area or network and multisensory processes. With its already large and fast increasing usage, future work using NIBS in isolation, as well as in conjunction with different neuroimaging techniques, could substantially improve our understanding of multisensory processing in the human brain.

  10. Non-invasive screening for colorectal cancer in Asia.

    PubMed

    Chiu, Han-Mo; Chang, Li-Chun; Hsu, Wen-Feng; Chou, Chu-Kuang; Wu, Ming-Shiang

    2015-12-01

    There is an increasing trend of colorectal cancer incidence in Asia and nearly 45% of CRC cases worldwide occur in Asia therefore screening for CRC becomes an urgent task. Stool-based tests, including guaiac fecal occult blood test (gFOBT) and fecal immunochemical test (FIT), can select subjects at risk of significant colorectal neoplasms from the large target population thus are currently the most commonly used non-invasive screening tool in large population screening programs. FIT has the advantage over gFOBT in terms of higher sensitivity for early neoplasms, the ability to provide high-throughput automatic analysis, and better public acceptance thus greater effectiveness on reducing CRC mortality and incidence is expected. Owing to the large target population and constrained endoscopic capacity and manpower, FIT is nowadays the most popular CRC screening test in Asia. Some Asian countries have launched nationwide screening program in the past one or two decades but also encountered some challenges such as low screening participation rate, low verification rate after positive stool tests, low public awareness, and insufficient manpower. In addition, some controversial or potential future research issues are also addressed in this review.

  11. Non-invasive biomarkers of lung inflammation in smoking subjects.

    PubMed

    Malerba, M; Montuschi, P

    2012-01-01

    Cigarette smoking is the most important risk factor for the development of chronic obstructive pulmonary disease (COPD) and lung cancer, but only a part of smoking subjects develop these respiratory pathologies. Therefore, it is necessary to find sensible parameters to detect early lung alterations due to chronic tobacco smoke exposure. Long-term cigarette smoking is associated with a persistent inflammatory response in the lung that leads to tissue injury and dysfunction. Bronchoscopy and bronchial biopsies are the gold standard techniques for assessing pulmonary inflammation, but are invasive and not routinely used. Cellular analysis of induced sputum and measurement of fraction of exhaled nitric oxide (F(E)NO) are validated non-invasive techniques for assessing respiratory inflammation. Measurement of biomolecules in sputum supernatants and exhaled breath condensate (EBC) are used as a research tool, but require standardization of procedures and, generally, analytical validation. Electronic nose differentiates healthy smokers from healthy nonsmokers based on breath volatile organic compounds (VOC) patterns. These techniques are potentially useful for identifying biomarkers of pulmonary inflammation and oxidative stress. Induced sputum, F(E)NO, EBC and electronic nose are suitable for longitudinal sampling, thereby facilitating monitoring of lung damage process. This approach could enable an early identification of subgroups of healthy smokers at higher risk for tobacco-induced lung damage and prompt planning of secondary prevention strategies.

  12. Alteration of Political Belief by Non-invasive Brain Stimulation

    PubMed Central

    Chawke, Caroline; Kanai, Ryota

    2016-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to. PMID:26834603

  13. Non invasive in vivo investigation of hepatobiliary structure and function in STII medaka (Oryzias latipes): methodology and applications

    PubMed Central

    Hardman, Ron C; Kullman, Seth W; Hinton, David E

    2008-01-01

    Background A novel transparent stock of medaka (Oryzias latipes; STII), recessive for all pigments found in chromatophores, permits transcutaneous imaging of internal organs and tissues in living individuals. Findings presented describe the development of methodologies for non invasive in vivo investigation in STII medaka, and the successful application of these methodologies to in vivo study of hepatobiliary structure, function, and xenobiotic response, in both 2 and 3 dimensions. Results Using brightfield, and widefield and confocal fluorescence microscopy, coupled with the in vivo application of fluorescent probes, structural and functional features of the hepatobiliary system, and xenobiotic induced toxicity, were imaged at the cellular level, with high resolution (< 1 μm), in living individuals. The findings presented demonstrate; (1) phenotypic response to xenobiotic exposure can be investigated/imaged in vivo with high resolution (< 1 μm), (2) hepatobiliary transport of solutes from blood to bile can be qualitatively and quantitatively studied/imaged in vivo, (3) hepatobiliary architecture in this lower vertebrate liver can be studied in 3 dimensions, and (4) non invasive in vivo imaging/description of hepatobiliary development in this model can be investigated. Conclusion The non-invasive in vivo methodologies described are a unique means by which to investigate biological structure, function and xenobiotic response with high resolution in STII medaka. In vivo methodologies also provide the future opportunity to integrate molecular mechanisms (e.g., genomic, proteomic) of disease and toxicity with phenotypic changes at the cellular and system levels of biological organization. While our focus has been the hepatobiliary system, other organ systems are equally amenable to in vivo study, and we consider the potential for discovery, within the context of in vivo investigation in STII medaka, as significant. PMID:18838008

  14. Non-invasive quantification of lower limb mechanical alignment in flexion

    PubMed Central

    Deakin, Angela; Fogg, Quentin A.; Picard, Frederic

    2014-01-01

    Objective Non-invasive navigation techniques have recently been developed to determine mechanical femorotibial alignment (MFTA) in extension. The primary aim of this study was to evaluate the precision and accuracy of an image-free navigation system with new software designed to provide multiple kinematic measurements of the knee. The secondary aim was to test two types of strap material used to attach optical trackers to the lower limb. Methods Seventy-two registrations were carried out on 6 intact embalmed cadaveric specimens (mean age: 77.8 ± 12 years). A validated fabric strap, bone screws and novel rubber strap were used to secure the passive tracker baseplate for four full experiments with each knee. The MFTA angle was measured under the conditions of no applied stress, valgus stress, and varus stress. These measurements were carried out at full extension and at 30°, 40°, 50° and 60° of flexion. Intraclass correlation coefficients, repeatability coefficients, and limits of agreement (LOA) were used to convey precision and agreement in measuring MFTA with respect to each of the independent variables, i.e., degree of flexion, applied coronal stress, and method of tracker fixation. Based on the current literature, a repeatability coefficient and LOA of ≤3° were deemed acceptable. Results The mean fixed flexion for the 6 specimens was 12.8° (range: 6–20°). The mean repeatability coefficient measuring MFTA in extension with screws or fabric strapping of the baseplate was ≤2°, compared to 2.3° using rubber strapping. When flexing the knee, MFTA measurements taken using screws or fabric straps remained precise (repeatability coefficient ≤3°) throughout the tested range of flexion (12.8–60°); however, using rubber straps, the repeatability coefficient was >3° beyond 50° flexion. In general, applying a varus/valgus stress while measuring MFTA decreased precision beyond 40° flexion. Using fabric strapping, excellent repeatability

  15. Microwave Radiometry for Non-Invasive Detection of Vesicoureteral Reflux (VUR) Following Bladder Warming.

    PubMed

    Stauffer, Paul R; Maccarini, Paolo F; Arunachalam, Kavitha; De Luca, Valeria; Salahi, Sara; Boico, Alina; Klemetsen, Oystein; Birkelund, Yngve; Jacobsen, Svein K; Bardati, Fernando; Tognolatti, Piero; Snow, Brent

    2011-01-01

    BACKGROUND: Vesicoureteral reflux (VUR) is a serious health problem leading to renal scarring in children. Current VUR detection involves traumatic x-ray imaging of kidneys following injection of contrast agent into bladder via invasive Foley catheter. We present an alternative non-invasive approach for detecting VUR by radiometric monitoring of kidney temperature while gently warming the bladder. METHODS: We report the design and testing of: i) 915MHz square slot antenna array for heating bladder, ii) EMI-shielded log spiral microstrip receive antenna, iii) high-sensitivity 1.375GHz total power radiometer, iv) power modulation approach to increase urine temperature relative to overlying perfused tissues, and v) invivo porcine experiments characterizing bladder heating and radiometric temperature of aaline filled 30mL balloon "kidney" implanted 3-4cm deep in thorax and varied 2-6°C from core temperature. RESULTS: SAR distributions are presented for two novel antennas designed to heat bladder and monitor deep kidney temperatures radiometrically. We demonstrate the ability to heat 180mL saline in in vivo porcine bladder to 40-44°C while maintaining overlying tissues <38°C using time-modulated square slot antennas coupled to the abdomen with room temperature water pad. Pathologic evaluations confirmed lack of acute thermal damage in pelvic tissues for up to three 20min bladder heat exposures. The radiometer clearly recorded 2-6°C changes of 30mL "kidney" targets at depth in 34°C invivo pig thorax. CONCLUSION: A 915MHz antenna array can gently warm in vivo pig bladder without toxicity while a 1.375GHz radiometer with log spiral receive antenna detects ≥2°C rise in 30mL "urine" located 3-4cm deep in thorax, demonstrating more than sufficient sensitivity to detect Grade 4-5 reflux of warmed urine for non-invasive detection of VUR.

  16. Non-invasive diagnosis of hepatitis B virus-related cirrhosis

    PubMed Central

    Lee, Sangheun; Kim, Do Young

    2014-01-01

    Chronic hepatitis B (CHB) infection is a major public health problem associated with significant morbidity and mortality worldwide. Twenty-three percent of patients with CHB progress naturally to liver cirrhosis, which was earlier thought to be irreversible. However, it is now known that cirrhosis can in fact be reversed by treatment with oral anti-nucleotide drugs. Thus, early and accurate diagnosis of cirrhosis is important to allow an appropriate treatment strategy to be chosen and to predict the prognosis of patients with CHB. Liver biopsy is the reference standard for assessment of liver fibrosis. However, the method is invasive, and is associated with pain and complications that can be fatal. In addition, intra- and inter-observer variability compromises the accuracy of liver biopsy data. Only small tissue samples are obtained and fibrosis is heterogeneous in such samples. This confounds the two types of observer variability mentioned above. Such limitations have encouraged development of non-invasive methods for assessment of fibrosis. These include measurements of serum biomarkers of fibrosis; and assessment of liver stiffness via transient elastography, acoustic radiation force impulse imaging, real-time elastography, or magnetic resonance elastography. Although significant advances have been made, most work to date has addressed the diagnostic utility of these techniques in the context of cirrhosis caused by chronic hepatitis C infection. In the present review, we examine the advantages afforded by use of non-invasive methods to diagnose cirrhosis in patients with CHB infections and the utility of such methods in clinical practice. PMID:24574713

  17. Microwave radiometry for non-invasive detection of vesicoureteral reflux (VUR) following bladder warming

    NASA Astrophysics Data System (ADS)

    Stauffer, Paul R.; Maccarini, Paolo F.; Arunachalam, Kavitha; De Luca, Valeria; Salahi, Sara; Boico, Alina; Klemetsen, Oystein; Birkelund, Yngve; Jacobsen, Svein K.; Bardati, Fernando; Tognolotti, Piero; Snow, Brent

    2011-03-01

    Background: Vesicoureteral reflux (VUR) is a serious health problem leading to renal scarring in children. Current VUR detection involves traumatic x-ray imaging of kidneys following injection of contrast agent into bladder via invasive Foley catheter. We present an alternative non-invasive approach for detecting VUR by radiometric monitoring of kidney temperature while gently warming the bladder. Methods: We report the design and testing of: i) 915MHz square slot antenna array for heating bladder, ii) EMI-shielded log spiral microstrip receive antenna, iii) high-sensitivity 1.375GHz total power radiometer, iv) power modulation approach to increase urine temperature relative to overlying perfused tissues, and v) invivo porcine experiments characterizing bladder heating and radiometric temperature of aaline filled 30mL balloon "kidney" implanted 3-4cm deep in thorax and varied 2-6°C from core temperature. Results: SAR distributions are presented for two novel antennas designed to heat bladder and monitor deep kidney temperatures radiometrically. We demonstrate the ability to heat 180mL saline in in vivo porcine bladder to 40-44°C while maintaining overlying tissues <38°C using time-modulated square slot antennas coupled to the abdomen with room temperature water pad. Pathologic evaluations confirmed lack of acute thermal damage in pelvic tissues for up to three 20min bladder heat exposures. The radiometer clearly recorded 2-6°C changes of 30mL "kidney" targets at depth in 34°C invivo pig thorax. Conclusion: A 915MHz antenna array can gently warm in vivo pig bladder without toxicity while a 1.375GHz radiometer with log spiral receive antenna detects >=2°C rise in 30mL "urine" located 3-4cm deep in thorax, demonstrating more than sufficient sensitivity to detect Grade 4-5 reflux of warmed urine for non-invasive detection of VUR.

  18. Non-invasive computation of aortic pressure maps: a phantom-based study of two approaches

    NASA Astrophysics Data System (ADS)

    Delles, Michael; Schalck, Sebastian; Chassein, Yves; Müller, Tobias; Rengier, Fabian; Speidel, Stefanie; von Tengg-Kobligk, Hendrik; Kauczor, Hans-Ulrich; Dillmann, Rüdiger; Unterhinninghofen, Roland

    2014-03-01

    Patient-specific blood pressure values in the human aorta are an important parameter in the management of cardiovascular diseases. A direct measurement of these values is only possible by invasive catheterization at a limited number of measurement sites. To overcome these drawbacks, two non-invasive approaches of computing patient-specific relative aortic blood pressure maps throughout the entire aortic vessel volume are investigated by our group. The first approach uses computations from complete time-resolved, three-dimensional flow velocity fields acquired by phasecontrast magnetic resonance imaging (PC-MRI), whereas the second approach relies on computational fluid dynamics (CFD) simulations with ultrasound-based boundary conditions. A detailed evaluation of these computational methods under realistic conditions is necessary in order to investigate their overall robustness and accuracy as well as their sensitivity to certain algorithmic parameters. We present a comparative study of the two blood pressure computation methods in an experimental phantom setup, which mimics a simplified thoracic aorta. The comparative analysis includes the investigation of the impact of algorithmic parameters on the MRI-based blood pressure computation and the impact of extracting pressure maps in a voxel grid from the CFD simulations. Overall, a very good agreement between the results of the two computational approaches can be observed despite the fact that both methods used completely separate measurements as input data. Therefore, the comparative study of the presented work indicates that both non-invasive pressure computation methods show an excellent robustness and accuracy and can therefore be used for research purposes in the management of cardiovascular diseases.

  19. Non-invasive determination of absolute lung resistivity in adults using electrical impedance tomography.

    PubMed

    Zhang, Jie; Patterson, Robert

    2010-08-01

    Lung resistivity is a physiological parameter that describes the electrical characteristics of the lungs. Lung composition changes due to changes in the lung tissues, fluid and air volume. Various diseases that can cause a change in lung composition may be monitored by measuring lung resistivity. Currently, there is no accepted non-invasive method to measure lung resistivity. In this study, we presented a method and framework to non-invasively determine lung resistivity using electrical impedance tomography (EIT). By comparing actual measurements from subjects with data from a 3D human thorax model, an EIT image can be reconstructed to show a resistivity difference between the model and the subject. By adjusting the lung resistivity in the model, the resistivity difference in the lung regions can be reduced to near zero. This resistivity value then is the estimation of the lung resistivity of the subject. Using the proposed method, the lung resistivities of four normal adult males (43 +/- 13 years, 78 +/- 10 kg) in the supine position at air volumes starting at functional residual capacity (FRC--end expiration) and increasing in 0.5 l steps to 1.5 l were studied. The averaged lung resistivity changes 12.59%, from 1406 Omega cm to 1583 Omega cm, following the inspiration of 1.5 l air from FRC. The coefficients of variation (CV) of precision for the four subjects are less than 10%. The experiment was repeated five times at each air volume on a subject to test the reproducibility. The CVs are less than 3%. The results show that it is feasible to determine absolute lung resistivity using an EIT-based method.

  20. The capability of fluoroscopic systems to determine differential Roentgen-ray absorption

    NASA Technical Reports Server (NTRS)

    Baily, N. A.; Crepeau, R. L.

    1975-01-01

    A clinical fluoroscopic unit used in conjunction with a TV image digitization system was investigated to determine its capability to evaluate differential absorption between two areas in the same field. Fractional contrasts and minimum detectability for air, several concentrations of Renografin-60, and aluminum were studied using phantoms of various thicknesses. Results showed that the videometric response, when treated as contrast, shows a linear response with absorber thickness up to considerable thicknesses.

  1. FLUOROSCOPIC EVALUATION OF ORO-PHARYNGEAL DYSPHAGIA: ANATOMY, TECHNIQUE, AND COMMON ETIOLOGIES

    PubMed Central

    Edmund, Dr; Au, Frederick Wing-Fai; Steele, Catriona M.

    2015-01-01

    Target Audience Radiologists and other professionals involved in imaging of oropharyngeal swallowing Objectives To review anatomy of the upper GI tract To review techniques and contrast agents used in the fluoroscopic examination of the oropharynx and hypopharynx To provide a pictorial review of some important causes of oropharyngeal dysphagia, and to link these to key findings in the clinical history to assist in establishing a clinical diagnosis To provide self-assessment questions to reinforce key learning points PMID:25539237

  2. Red blood cell as a universal optoacoustic sensor for non-invasive temperature monitoring

    NASA Astrophysics Data System (ADS)

    Petrova, Elena V.; Oraevsky, Alexander A.; Ermilov, Sergey A.

    2014-09-01

    Optoacoustic (photoacoustic) temperature imaging could provide improved spatial resolution and temperature sensitivity as compared to other techniques of non-invasive thermometry used during thermal therapies for safe and efficient treatment of lesions. However, accuracy of the reported optoacoustic methods is compromised by biological variability and heterogeneous composition of tissues. We report our findings on the universal character of the normalized temperature dependent optoacoustic response (ThOR) in blood, which is invariant with respect to hematocrit at the isosbestic point of hemoglobin. The phenomenon is caused by the unique homeostatic compartmentalization of blood hemoglobin exclusively inside erythrocytes. On the contrary, the normalized ThOR in aqueous solutions of hemoglobin showed linear variation with respect to its concentration and was identical to that of blood when extrapolated to the hemoglobin concentration inside erythrocytes. To substantiate the conclusions, we analyzed optoacoustic images acquired from the samples of whole and diluted blood as well as hemoglobin solutions during gradual cooling from +37 to -15 °C. Our experimental methodology allowed direct observation and accurate measurement of the temperature of zero optoacoustic response, manifested as the sample's image faded into background and then reappeared in the reversed (negative) contrast. These findings provide a framework necessary for accurate correlation of measured normalized optoacoustic image intensity and local temperature in vascularized tissues independent of tissue composition.

  3. Red blood cell as a universal optoacoustic sensor for non-invasive temperature monitoring

    PubMed Central

    Petrova, Elena V.; Oraevsky, Alexander A.; Ermilov, Sergey A.

    2014-01-01

    Optoacoustic (photoacoustic) temperature imaging could provide improved spatial resolution and temperature sensitivity as compared to other techniques of non-invasive thermometry used during thermal therapies for safe and efficient treatment of lesions. However, accuracy of the reported optoacoustic methods is compromised by biological variability and heterogeneous composition of tissues. We report our findings on the universal character of the normalized temperature dependent optoacoustic response (ThOR) in blood, which is invariant with respect to hematocrit at the isosbestic point of hemoglobin. The phenomenon is caused by the unique homeostatic compartmentalization of blood hemoglobin exclusively inside erythrocytes. On the contrary, the normalized ThOR in aqueous solutions of hemoglobin showed linear variation with respect to its concentration and was identical to that of blood when extrapolated to the hemoglobin concentration inside erythrocytes. To substantiate the conclusions, we analyzed optoacoustic images acquired from the samples of whole and diluted blood as well as hemoglobin solutions during gradual cooling from +37 to −15 °C. Our experimental methodology allowed direct observation and accurate measurement of the temperature of zero optoacoustic response, manifested as the sample's image faded into background and then reappeared in the reversed (negative) contrast. These findings provide a framework necessary for accurate correlation of measured normalized optoacoustic image intensity and local temperature in vascularized tissues independent of tissue composition. PMID:25316928

  4. Non-invasive Brain Stimulation for Essential Tremor

    PubMed Central

    Shih, Ludy C.; Pascual-Leone, Alvaro

    2017-01-01

    Background There is increasing interest in the use of non-invasive brain stimulation to characterize and potentially treat essential tremor (ET). Studies have used a variety of stimulation coils, paradigms, and target locations to make these observations. We reviewed the literature to compare prior studies and to evaluate the rationale and the methods used in these studies. Methods We performed a systematic literature search of the PubMed database using the terms “transcranial,” “noninvasive,” “brain stimulation,” “transcranial magnetic stimulation (TMS),” “transcranial direct current stimulation (tDCS),” “transcranial alternating current stimulation (tACS),” and “essential tremor.” Results Single pulses of TMS to the primary motor cortex have long been known to reset tremor. Although there are relatively few studies showing alterations in motor cortical physiology, such as motor threshold, short and long intracortical inhibition, and cortical silent period, there may be some evidence of altered intracortical facilitation and cerebello-brain inhibition in ET. Repetitive TMS, theta burst stimulation, tDCS, and tACS have been applied to human subjects with tremor with some preliminary signs of tremor reduction, particularly in those studies that employed consecutive daily sessions. Discussion A variety of stimulation paradigms and targets have been explored, with the increasing rationale an interest in targeting the cerebellum. Rigorous assessment of coil geometry, stimulation paradigm, rationale for selection of the specific anatomic target, and careful phenotypic and physiologic characterization of the subjects with ET undergoing these interventions may be critical in extending these preliminary findings into effective stimulation therapies. PMID:28373927

  5. Early non-invasive ventilation treatment for severe influenza pneumonia.

    PubMed

    Masclans, J R; Pérez, M; Almirall, J; Lorente, L; Marqués, A; Socias, L; Vidaur, L; Rello, J

    2013-03-01

    The role of non-invasive ventilation (NIV) in acute respiratory failure caused by viral pneumonia remains controversial. Our objective was to evaluate the use of NIV in a cohort of (H1N1)v pneumonia. Usefulness and success of NIV were assessed in a prospective, observational registry of patients with influenza A (H1N1) virus pneumonia in 148 Spanish intensive care units (ICUs) in 2009-10. Significant variables for NIV success were included in a multivariate analysis. In all, 685 patients with confirmed influenza A (H1N1)v viral pneumonia were admitted to participating ICUs; 489 were ventilated, 177 with NIV. The NIV was successful in 72 patients (40.7%), the rest required intubation. Low Acute Physiology and Chronic Health Evaluation (APACHE) II, low Sequential Organ Failure Assessment (SOFA) and absence of renal failure were associated with NIV success. Success of NIV was independently associated with fewer than two chest X-ray quadrant opacities (OR 3.5) and no vasopressor requirement (OR 8.1). However, among patients with two or more quadrant opacities, a SOFA score ≤7 presented a higher success rate than those with SOFA score >7 (OR 10.7). Patients in whom NIV was successful required shorter ventilation time, shorter ICU stay and hospital stay than NIV failure. In patients in whom NIV failed, the delay in intubation did not increase mortality (26.5% versus 24.2%). Clinicians used NIV in 25.8% of influenza A (H1N1)v viral pneumonia admitted to ICU, and treatment was effective in 40.6% of them. NIV success was associated with shorter hospital stay and mortality similar to non-ventilated patients. NIV failure was associated with a mortality similar to those who were intubated from the start.

  6. A novel probe for the non-invasive detection of tumor-associated inflammation

    PubMed Central

    Balducci, Anthony; Wen, Yi; Zhang, Yang; Helfer, Brooke M.; Hitchens, T. Kevin; Meng, Wilson S.; Wesa, Amy K.; Janjic, Jelena M.

    2013-01-01

    A novel dual-mode contrast agent was formulated through the addition of an optical near infrared (NIR) probe to a perfluorocarbon (PFC)-based 19F magnetic resonance imaging (MRI) agent, which labels inflammatory cells in situ. A single PFC-NIR imaging agent enables both a qualitative, rapid optical monitoring of an inflammatory state and a quantitative, detailed and tissue-depth independent magnetic resonance imaging (MRI). The feasibility of in vivo optical imaging of the inflammatory response was demonstrated in a subcutaneous murine breast carcinoma model. Ex vivo optical imaging was used to quantify the PFC-NIR signal in the tumor and organs, and results correlated well with quantitative 19F NMR analyses of intact tissues. 19F MRI was employed to construct a three-dimensional image of the cellular microenvironment at the tumor site. Flow cytometry of isolated tumor cells was used to identify the cellular localization of the PFC-NIR probe within the tumor microenvironment. Contrast is achieved through the labeling of host cells involved in the immune response, but not tumor cells. The major cellular reservoir of the imaging agent were tumor-infiltrating CD11b+ F4/80low Gr-1low cells, a cell subset sharing immunophenotypic features with myeloid-derived suppressor cells (MDSCs). These cells are recruited to sites of inflammation and are implicated in immune evasion and tumor progression. This PFC-NIR contrast agent coupled to non-invasive, quantitative imaging techniques could serve as a valuable tool for evaluating novel anticancer agents. PMID:23526711

  7. Non-Invasive Investigation of Bone Adaptation in Humans to Mechanical Loading

    NASA Technical Reports Server (NTRS)

    Whalen, R.

    1999-01-01

    Experimental studies have identified peak cyclic forces, number of loading cycles, and loading rate as contributors to the regulation of bone metabolism. We have proposed a theoretical model that relates bone density to a mechanical stimulus derived from average daily cumulative peak cyclic 'effective' tissue stresses. In order to develop a non-invasive experimental model to test the theoretical model we need to: (1) monitor daily cumulative loading on a bone, (2) compute the internal stress state(s) resulting from the imposed loading, and (3) image volumetric bone density accurately, precisely, and reproducibly within small contiguous volumes throughout the bone. We have chosen the calcaneus (heel) as an experimental model bone site because it is loaded by ligament, tendon and joint contact forces in equilibrium with daily ground reaction forces that we can measure; it is a peripheral bone site and therefore more easily and accurately imaged with computed tomography; it is composed primarily of cancellous bone; and it is a relevant site for monitoring bone loss and adaptation in astronauts and the general population. This paper presents an overview of our recent advances in the areas of monitoring daily ground reaction forces, biomechanical modeling of the forces on the calcaneus during gait, mathematical modeling of calcaneal bone adaptation in response to cumulative daily activity, accurate and precise imaging of the calcaneus with quantitative computed tomography (QCT), and application to long duration space flight.

  8. Feasibility of Using Wideband Microwave System for Non-Invasive Detection and Monitoring of Pulmonary Oedema

    NASA Astrophysics Data System (ADS)

    Rezaeieh, S. Ahdi; Zamani, A.; Bialkowski, K. S.; Mahmoud, A.; Abbosh, A. M.

    2015-09-01

    Pulmonary oedema is a common manifestation of various fatal diseases that can be caused by cardiac or non-cardiac syndromes. The accumulated fluid has a considerably higher dielectric constant compared to lungs’ tissues, and can thus be detected using microwave techniques. Therefore, a non-invasive microwave system for the early detection of pulmonary oedema is presented. It employs a platform in the form of foam-based bed that contains two linear arrays of wideband antennas covering the band 0.7-1 GHz. The platform is designed such that during the tests, the subject lays on the bed with the back of the torso facing the antenna arrays. The antennas are controlled using a switching network that is connected to a compact network analyzer. A novel frequency-based imaging algorithm is used to process the recorded signals and generate an image of the torso showing any accumulated fluids in the lungs. The system is verified on an artificial torso phantom, and animal organs. As a feasibility study, preclinical tests are conducted on healthy subjects to determinate the type of obtained images, the statistics and threshold levels of their intensity to differentiate between healthy and unhealthy subjects.

  9. Feasibility of Using Wideband Microwave System for Non-Invasive Detection and Monitoring of Pulmonary Oedema

    PubMed Central

    Rezaeieh, S. Ahdi; Zamani, A.; Bialkowski, K. S.; Mahmoud, A.; Abbosh, A. M.

    2015-01-01

    Pulmonary oedema is a common manifestation of various fatal diseases that can be caused by cardiac or non-cardiac syndromes. The accumulated fluid has a considerably higher dielectric constant compared to lungs’ tissues, and can thus be detected using microwave techniques. Therefore, a non-invasive microwave system for the early detection of pulmonary oedema is presented. It employs a platform in the form of foam-based bed that contains two linear arrays of wideband antennas covering the band 0.7–1 GHz. The platform is designed such that during the tests, the subject lays on the bed with the back of the torso facing the antenna arrays. The antennas are controlled using a switching network that is connected to a compact network analyzer. A novel frequency-based imaging algorithm is used to process the recorded signals and generate an image of the torso showing any accumulated fluids in the lungs. The system is verified on an artificial torso phantom, and animal organs. As a feasibility study, preclinical tests are conducted on healthy subjects to determinate the type of obtained images, the statistics and threshold levels of their intensity to differentiate between healthy and unhealthy subjects. PMID:26365299

  10. Non-invasive quantification of small bowel water content by MRI: a validation study

    NASA Astrophysics Data System (ADS)

    Hoad, C. L.; Marciani, L.; Foley, S.; Totman, J. J.; Wright, J.; Bush, D.; Cox, E. F.; Campbell, E.; Spiller, R. C.; Gowland, P. A.

    2007-12-01

    Substantial water fluxes across the small intestine occur during digestion of food, but so far measuring these has required invasive intubation techniques. This paper describes a non-invasive magnetic resonance imaging (MRI) technique for measuring small bowel water content which has been validated using naso-duodenal infusion. Eighteen healthy volunteers were intubated, with the tube position being verified by MRI. After a baseline MRI scan, each volunteer had eight 40 ml boluses of a non-absorbable mannitol and saline solution infused into their proximal small bowel with an MRI scan being acquired after each bolus. The MRI sequence used was an adapted magnetic resonance cholangiopancreatography sequence. The image data were thresholded to allow for intra- and inter-subject signal variations. The MRI measured volumes were then compared to the known infused volumes. This MRI technique gave excellent images of the small bowel, which closely resemble those obtained using conventional radiology with barium contrast. The mean difference between the measured MRI volumes and infused volumes was 2% with a standard deviation of 10%. The maximum 95% limits of agreement between observers were -15% to +17% while measurements by the same operator on separate occasions differed by only 4%. This new technique can now be applied to study alterations in small bowel fluid absorption and secretion due to gastrointestinal disease or drug intervention.

  11. Digital Subtraction Fluoroscopic System With Tandem Video Processing Units

    NASA Astrophysics Data System (ADS)

    Gould, Robert G.; Lipton, Martin J.; Mengers, Paul; Dahlberg, Roger

    1981-07-01

    A real-time digital fluoroscopic system utilizing two video processing units (Quantex) in tandem to produce continuous subtraction images of peripheral and internal vessels following intravenous contrast media injection has been inves-tigated. The first processor subtracts a mask image consisting of an exponentially weighted moving average of N1 frames (N1 = 2k where k = 0.7) from each incoming video frame, divides by N1, and outputs the resulting difference image to the second processor. The second unit continuously averages N2 incoming frames (N2 = 2k) and outputs to a video monitor and analog disc recorder. The contrast of the subtracted images can be manipulated by changing gain or by a non-linear output transform. After initial equipment adjustments, a subtraction sequence can be produced without operator interaction with the processors. Alternatively, the operator can freeze the mask and/or the subtracted output image at any time during the sequence. Raw data is preserved on a wide band video tape recorder permitting retrospective viewing of an injection sequence with different processor settings. The advantage of the tandem arrangement is that it has great flexibility in varying the duration and the time of both the mask and injection images thereby minimizing problems of registration between them. In addition, image noise is reduced by compiling video frames rather than by using a large radiation dose for a single frame, which requires a wide dynamic range video camera riot commonly available in diagnostic x-ray equipment. High quality subtraction images of arteries have been obtained in 15 anesthetized dogs using relatively low exposure rates (10-12 μR/video frame) modest volumes of contrast medium (0.5-1 ml/kg), and low injection flow rates (6-10 ml/sec). The results/ achieved so far suggest that this system has direct clinical applications.

  12. A small, battery-operated fluoroscopic system - Lixiscope with X-ray generator

    NASA Technical Reports Server (NTRS)

    Yin, L. I.; Trombka, J. I.; Ruitberg, A. P.; Seltzer, S. M.

    1983-01-01

    A small, battery-operated X-ray generator has been developed to be used as part of a small-format fluoroscopic system, the Lixiscope (Low Intensity X-ray Imaging Scope). The X-ray generator consists of a grounded rod-anode X-ray tube with a 0.2 mm focal spot and a specially designed, battery-operated, 0 to -80 kV high-voltge supply. Total power consumption is about 10 W. The fine focal spot, in conjunction with the continuously variable X-ray intensity and spectral distribution, helps to extend both the versatility and the performance of the Lixiscope toward a much wider range of terrestrial and spacecraft applications. The complete fluoroscopic system is described, and some examples of possible applications are shown.

  13. Non-invasive ventilation in acute respiratory failure in children

    PubMed Central

    Abadesso, Clara; Nunes, Pedro; Silvestre, Catarina; Matias, Ester; Loureiro, Helena; Almeida, Helena

    2012-01-01

    The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO2 at 2, 6, 12 and 24 hours after NIV onset (P<0.05) in both groups. Improvement in pulse oximetric saturation/fraction of inspired oxygen (SpO2/FiO2) was verified at 2, 4, 6, 12 and 24 hours after NIV onset in the success group (P<0.001). In the failure group, significant SpO2/FiO2 improvement was only observed in the first 4 hours. NIV failure occurred in 34 patients (22.5%). Risk factors for NIV failure were apnea, prematurity, pneumonia, and bacterial co-infection (P<0.05). Independent risk factors for NIV failure were apneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42–71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33–111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection. PMID:22802994

  14. Non-invasive assessment of Alzheimer's disease neurofibrillary pathology using 18F-THK5105 PET.

    PubMed

    Okamura, Nobuyuki; Furumoto, Shozo; Fodero-Tavoletti, Michelle T; Mulligan, Rachel S; Harada, Ryuichi; Yates, Paul; Pejoska, Svetlana; Kudo, Yukitsuka; Masters, Colin L; Yanai, Kazuhiko; Rowe, Christopher C; Villemagne, Victor L

    2014-06-01

    Non-invasive imaging of tau pathology in the living brain would be useful for accurately diagnosing Alzheimer's disease, tracking disease progression, and evaluating the treatment efficacy of disease-specific therapeutics. In this study, we evaluated the clinical usefulness of a novel tau-imaging positron emission tomography tracer 18F-THK5105 in 16 human subjects including eight patients with Alzheimer's disease (three male and five females, 66-82 years) and eight healthy elderly controls (three male and five females, 63-76 years). All participants underwent neuropsychological examination and 3D magnetic resonance imaging, as well as both 18F-THK5105 and 11C-Pittsburgh compound B positron emission tomography scans. Standard uptake value ratios at 90-100 min and 40-70 min post-injection were calculated for 18F-THK5105 and 11C-Pittsburgh compound B, respectively, using the cerebellar cortex as the reference region. As a result, significantly higher 18F-THK5105 retention was observed in the temporal, parietal, posterior cingulate, frontal and mesial temporal cortices of patients with Alzheimer's disease compared with healthy control subjects. In patients with Alzheimer's disease, the inferior temporal cortex, which is an area known to contain high densities of neurofibrillary tangles in the Alzheimer's disease brain, showed prominent 18F-THK5105 retention. Compared with high frequency (100%) of 18F-THK5105 retention in the temporal cortex of patients with Alzheimer's disease, frontal 18F-THK5105 retention was less frequent (37.5%) and was only observed in cases with moderate-to-severe Alzheimer's disease. In contrast, 11C-Pittsburgh compound B retention was highest in the posterior cingulate cortex, followed by the ventrolateral prefrontal, anterior cingulate, and superior temporal cortices, and did not correlate with 18F-THK5105 retention in the neocortex. In healthy control subjects, 18F-THK5105 retention was ∼10% higher in the mesial temporal cortex than in the

  15. Robust Fluoroscopic Tracking of Fiducial Markers: Exploiting the Spatial Constraints

    PubMed Central

    Li, Rui; Sharp, Gregory

    2013-01-01

    Two new fluoroscopic fiducial tracking methods that exploit the spatial relationship among the multiple implanted fiducial to achieve fast, accurate and robust tracking are proposed in this paper. The spatial relationship between multiple implanted markers are modeled as Gaussian distributions of their pairwise distances over time. The means and standard deviations of these distances are learned from training sequences, and pairwise distances that deviate from these learned distributions are assigned a low spatial matching score. The spatial constraints are incorporated in two different algorithms: a stochastic tracking method and a detection based method. In the stochastic method, hypotheses of the “true” fiducial position are sampled from a pre-trained respiration motion model. Each hypothesis is assigned an importance value based on image matching score and spatial matching score. Learning the parameters of the motion model is needed in addition to the learning the distribution parameters of the pairwise distances in the proposed stochastic tracking approach. In the detection based method, a set of possible marker locations are identified by using a template matching based fiducial detector. The best location is obtained by optimizing the image matching score and spatial matching score through non-serial dynamic programming. In this detection based approach, there is no need to learn the respiration motion model. The two proposed algorithms are compared with a recent work using multiple hypothesis tracking algorithm which is denoted by MHT[19]. Phantom experiments were performed using fluoroscopic videos captured with known motion relative to an anthropomorphic phantom. The patient experiments were performed using a retrospective study of 16 fluoroscopic videos of liver cancer patients with implanted fiducials. For the motion phantom data sets, the detection based approach has the smallest tracking error (μerr: 0.78 – 1.74 mm, σerr: 0.39 – 1.16 mm) for

  16. Non-invasive monitoring of hemodynamic changes in orthotropic brain tumor

    NASA Astrophysics Data System (ADS)

    Kashyap, Dheerendra; Sharma, Vikrant; Liu, Hanli

    2007-02-01

    Radio surgical interventions such as Gamma Knife and Cyberknife have become attractive as therapeutic interventions. However, one of the drawbacks of cyberknife is radionecrosis, which is caused by excessive radiation to surrounding normal tissues. Radionecrosis occurs in about 10-15% of cases and could have adverse effects leading to death. Currently available imaging techniques have failed to reliably distinguish radionecrosis from tumor growth. Development of imaging techniques that could provide distinction between tumor growth and radionecrosis would give us ability to monitor effects of radiation therapy non-invasively. This paper investigates the use of near infrared spectroscopy (NIRS) as a new technique to monitor the growth of brain tumors. Brain tumors (9L glioma cell line) were implanted in right caudate nucleus of rats (250-300 gms, Male Fisher C) through a guide screw. A new algorithm was developed, which used broadband steady-state reflectance measurements made using a single source-detector pair, to quantify absolute concentrations of hemoglobin derivatives and reduced scattering coefficients. Preliminary results from the brain tumors indicated decreases in oxygen saturation, oxygenated hemoglobin concentrations and increases in deoxygenated hemoglobin concentrations with tumor growth. The study demonstrates that NIRS technology could provide an efficient, noninvasive means of monitoring vascular oxygenation dynamics of brain tumors and further facilitate investigations of efficacy of tumor treatments.

  17. Non-invasive detection of periodontal disease using diffuse reflectance spectroscopy: a clinical study

    NASA Astrophysics Data System (ADS)

    Prasanth, Chandra Sekhar; Betsy, Joseph; Subhash, Narayanan; Jayanthi, Jayaraj L.; Prasanthila, Janam

    2012-03-01

    In clinical diagnostic procedures, gingival inflammation is considered as the initial stage of periodontal breakdown. This is often detected clinically by bleeding on probing as it is an objective measure of inflammation. Since conventional diagnostic procedures have several inherent drawbacks, development of novel non-invasive diagnostic techniques assumes significance. This clinical study was carried out in 15 healthy volunteers and 25 patients to demonstrate the applicability of diffuse reflectance (DR) spectroscopy for quantification and discrimination of various stages of inflammatory conditions in periodontal disease. The DR spectra of diseased lesions recorded using a point monitoring system consisting of a tungsten halogen lamp and a fiber-optic spectrometer showed oxygenated hemoglobin absorption dips at 545 and 575 nm. Mean DR spectra on normalization shows marked differences between healthy and different stages of gingival inflammation. Among the various DR intensity ratios investigated, involving oxy Hb absorption peaks, the R620/R575 ratio was found to be a good parameter of gingival inflammation. In order to screen the entire diseased area and its surroundings instantaneously, DR images were recorded with an EMCCD camera at 620 and 575 nm. We have observed that using the DR image intensity ratio R620/R575 mild inflammatory tissues could be discriminated from healthy with a sensitivity of 92% and specificity of 93%, and from moderate with a sensitivity of 83% and specificity of 96%. The sensitivity and specificity obtained between moderate and severe inflammation are 82% and 76% respectively.

  18. Spectrophotometric system to develop a non-invasive method for monitoring of posidonia oceanica meadows

    NASA Astrophysics Data System (ADS)

    Menesatti, P.; Urbani, G.; Dolce, T.

    2007-09-01

    Posidonia oceanica (L.) is an endemic phanerogam of the Mediterranean Sea. It lives between 0.2 and 40 m depth and make up extensive meadows that play a fundamental role in the marine coast ecosystem. Near the coasts at higher anthropic pressure, Posidonia meadows present both quality and quantity damages (regression) due to the mechanical operations on the seabed (anchoring, drag netting, pipe lines) and the sea pollution. Nowadays, the seagrass regression is monitored by different systems: aereophotografic, side scan sonar, underwater television camera, direct underwater visual inspection. Scientific community is looking for to develop monitoring systems more reliable, rapid and non invasive. Aim of this study is to evaluate the application of a new spectrophotometric imaging system based on the acquisition of reflectance spectral images with a good optical (250 Kpixels) and spectral resolution (spectral range 400-970 nm, a total of 115 single wavelength, 5 nm step each one). First trials were made on Posidonia's leafs to evaluate the system capacity to recognize spectral differences between samples picked up at two different depths (0.3 - 4 m). High discrimination percentage (90%) were found between leaf samples as function of the different depths, analyzing the spectral data by Partial Least Squares model. Forward activities will stress the system capability also to evaluate different phenol concentrations on Posidonia leaves, an important index of physiologic vegetal damage, through direct underwater spectrophotometric monitoring.

  19. MRI mediated, non-invasive tracking of intratumoral distribution of nanocarriers in rat glioma

    NASA Astrophysics Data System (ADS)

    Karathanasis, Efstathios; Park, Jaekeun; Agarwal, Abhiruchi; Patel, Vijal; Zhao, Fuqiang; Annapragada, Ananth V.; Hu, Xiaoping; Bellamkonda, Ravi V.

    2008-08-01

    Nanocarrier mediated therapy of gliomas has shown promise. The success of systemic nanocarrier-based chemotherapy is critically dependent on the so-called leaky vasculature to permit drug extravasation across the blood-brain barrier. Yet, the extent of vascular permeability in individual tumors varies widely, resulting in a correspondingly wide range of responses to the therapy. However, there exist no tools currently for rationally determining whether tumor blood vessels are amenable to nanocarrier mediated therapy in an individualized, patient specific manner today. To address this need for brain tumor therapy, we have developed a multifunctional 100 nm scale liposomal agent encapsulating a gadolinium-based contrast agent for contrast-enhanced magnetic resonance imaging with prolonged blood circulation. Using a 9.4 T MRI system, we were able to track the intratumoral distribution of the gadolinium-loaded nanocarrier in a rat glioma model for a period of three days due to improved magnetic properties of the contrast agent being packaged in a nanocarrier. Such a nanocarrier provides a tool for non-invasively assessing the suitability of tumors for nanocarrier mediated therapy and then optimizing the treatment protocol for each individual tumor. Additionally, the ability to image the tumor in high resolution can potentially constitute a surgical planning tool for tumor resection.

  20. Non-invasive differentiation of kidney stone types using X-ray dark-field radiography.

    PubMed

    Scherer, Kai; Braig, Eva; Willer, Konstantin; Willner, Marian; Fingerle, Alexander A; Chabior, Michael; Herzen, Julia; Eiber, Matthias; Haller, Bernhard; Straub, Michael; Schneider, Heike; Rummeny, Ernst J; Noël, Peter B; Pfeiffer, Franz

    2015-04-15

    Treatment of renal calculi is highly dependent on the chemical composition of the stone in question, which is difficult to determine using standard imaging techniques. The objective of this study is to evaluate the potential of scatter-sensitive X-ray dark-field radiography to differentiate between the most common types of kidney stones in clinical practice. Here, we examine the absorption-to-scattering ratio of 118 extracted kidney stones with a laboratory Talbot-Lau Interferometer. Depending on their chemical composition, microscopic growth structure and morphology the various types of kidney stones show strongly varying, partially opposite contrasts in absorption and dark-field imaging. By assessing the microscopic calculi morphology with high resolution micro-computed tomography measurements, we illustrate the dependence of dark-field signal strength on the respective stone type. Finally, we utilize X-ray dark-field radiography as a non-invasive, highly sensitive (100%) and specific (97%) tool for the differentiation of calcium oxalate, uric acid and mixed types of stones, while additionally improving the detectability of radio-lucent calculi. We prove clinical feasibility of the here proposed method by accurately classifying renal stones, embedded within a fresh pig kidney, using dose-compatible measurements and a quick and simple visual inspection.

  1. Non-invasive detection of periodontal loss of attachment using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Damodaran, Vani; Vasa, Nilesh J.; Sarathi, R.; Rao, Suresh Ranga

    2015-06-01

    This study aims at developing a non-invasive technique to evaluate periodontal loss of attachment in the oral cavity. A method of imaging periodontal loss of attachment based on time-domain optical coherence tomography is proposed and studied. Based on measurements, boundaries of gingival tissue and tooth were seen separated by ≈0.3 mm. Further study is in progress to image the anatomical landmarks and evaluate the periodontal loss of attachment. The conventional time domain OCT systems acquisition speed is limited by the speed of the mechanical scanning system. In order to overcome this issue, a novel electro-optic based scanning system is proposed and demonstrated. Studies were performed initially with lithium niobate and potassium titanyl phosphate crystals and the tuning range observed were low. In order to increase the tuning range, a crystal with high electro-optic coefficient - potassium tantalite niobate was identified and experiments were carried out to characterise the crystal and electro-optic based phase tuning is demonstrated.

  2. Towards Effective Non-Invasive Brain-Computer Interfaces Dedicated to Gait Rehabilitation Systems

    PubMed Central

    Castermans, Thierry; Duvinage, Matthieu; Cheron, Guy; Dutoit, Thierry

    2014-01-01

    In the last few years, significant progress has been made in the field of walk rehabilitation. Motor cortex signals in bipedal monkeys have been interpreted to predict walk kinematics. Epidural electrical stimulation in rats and in one young paraplegic has been realized to partially restore motor control after spinal cord injury. However, these experimental trials are far from being applicable to all patients suffering from motor impairments. Therefore, it is thought that more simple rehabilitation systems are desirable in the meanwhile. The goal of this review is to describe and summarize the progress made in the development of non-invasive brain-computer interfaces dedicated to motor rehabilitation systems. In the first part, the main principles of human locomotion control are presented. The paper then focuses on the mechanisms of supra-spinal centers active during gait, including results from electroencephalography, functional brain imaging technologies [near-infrared spectroscopy (NIRS), functional magnetic resonance imaging (fMRI), positron-emission tomography (PET), single-photon emission-computed tomography (SPECT)] and invasive studies. The first brain-computer interface (BCI) applications to gait rehabilitation are then presented, with a discussion about the different strategies developed in the field. The challenges to raise for future systems are identified and discussed. Finally, we present some proposals to address these challenges, in order to contribute to the improvement of BCI for gait rehabilitation. PMID:24961699

  3. Non-invasive estimation of coral tentacle material properties using underwater PIV data

    NASA Astrophysics Data System (ADS)

    Staples, Anne; Asher, Shai; Shavit, Uri

    2016-11-01

    With corals worldwide currently undergoing a third global bleaching event, understanding a detailed picture of local coral colony flow transport processes is more crucial than ever. Many coral species invest energy in extending flexible organs such as tentacles, that extrude from the coral's soft tissue surface and are used in either a passive or active manner for feeding, competitor sensing and even egg release. The significant role of these organs in transport and mixing processes is just beginning to be understood. For example, Xeniidea's rhythmic pulsation of its tentacles has recently been shown to intensify mixing and enhance photosynthesis (Kremien et al., 2013). A critical part of modeling these tentacle-induced flows is obtaining measurements of the tentacles' material properties. Obtaining such measurements, however, is challenging, since the tentacle is expected to have significantly different material properties than a harvested specimen. Here, we demonstrate a non-invasive, in situ approach for estimating these material properties forFavia favus tentacles using underwater particle image velocimetry (PIV) data and tentacle-tracking data, along with structural dynamics models of the tentacles. In this data, 2.7x2 [cm2] 1392x1024 pixel images were collected at a rate of 5 Hz 7mm above the crest of two separate Favia Favuscolonies in Eilat, Israel. Using the data and models, we are able to estimate the Young's modulus for the tentacles, which is found to be a function of the wave frequency. Partial funding by the Fulbright and Israel Science Foundations.

  4. Graft revascularization is essential for non-invasive monitoring of transplanted islets with radiolabeled exendin

    PubMed Central

    Eter, Wael A.; Bos, Desirée; Frielink, Cathelijne; Boerman, Otto C.; Brom, Maarten; Gotthardt, Martin

    2015-01-01

    Islet transplantation is a novel promising strategy to cure type 1 diabetes. However, the long-term outcome is still poor, because both function and survival of the transplant decline over-time. Non-invasive imaging methods have the potential to enable monitoring of islet survival after transplantation and the effects of immunosuppressive drugs on transplantation outcome. 111In-labeled exendin-3 is a promising tracer to visualize native and transplanted islets by SPECT (Single Photon Emission Computed Tomography). In the present study, we hypothesized that islet microvasculature plays an important role determining the uptake of exendin-3 in islets when monitoring transplant survival. We observed 111In-exendin-3 accumulation in the transplant as early as three days after transplantation and an increase in the uptake up to three weeks post-transplantation. Islet-revascularization correlated with the increase in 111In-exendin-3 uptake, whereas fully re-established islet vasculature coincided with a stabilized uptake of the radiotracer in the transplant. Here, we demonstrate the importance of islet vasculature for in vivo delivery of radiotracers to transplanted islets and we demonstrate that optimal and stable uptake of exendin four weeks after transplantation opens the possibility for long-term monitoring of islet survival by SPECT imaging. PMID:26490110

  5. Graft revascularization is essential for non-invasive monitoring of transplanted islets with radiolabeled exendin.

    PubMed

    Eter, Wael A; Bos, Desirée; Frielink, Cathelijne; Boerman, Otto C; Brom, Maarten; Gotthardt, Martin

    2015-10-22

    Islet transplantation is a novel promising strategy to cure type 1 diabetes. However, the long-term outcome is still poor, because both function and survival of the transplant decline over-time. Non-invasive imaging methods have the potential to enable monitoring of islet survival after transplantation and the effects of immunosuppres