Dissertations / Theses: 'Tissue imaging'

1

Killich, Markus. "Tissue Doppler Imaging." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-67089.

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Einarsdóttir, Hildur. "Imaging of soft tissue tumors /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-647-2/.

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Sharma, Srikanta. "Microultrasound imaging of tissue dysplasia." Thesis, University of Dundee, 2015. https://discovery.dundee.ac.uk/en/studentTheses/ce30ac7f-8d18-464d-bbe5-5e9329ff5ff2.

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The second most common cause of cancer deaths in the developed world is bowel cancer. Improving the ability to detect and classify lesions as early as possible, allows treatment earlier. The work presented in this thesis is structured around the following detailed aims:Development of high frequency, broadband µUS (micro-ultrasound) imaging transducers through optimization of ultra-thinning processes for lithium niobate (LNO) and fabrication of novel ‘mass-spring’ matching layers using carefully controlled vacuum deposition is demonstrated. The effectiveness of this technique was quantified by applying multiple matching layers to 3 mm diameter 45 MHz LNO µUS transducers using carefully controlled vacuum deposition. The bandwidth of single mass-spring layer µUS transducer was measured to be 46% with an insertion loss of 21 dB. The bandwidth and insertion loss of a multiple matching layer µUS transducer was measured to be 59% and 18 dB respectively. The values were compared with an unmatched transducer which had a bandwidth and insertion loss of 28% and 34 dB respectively. All the experimentally measured values were in agreement with unidimensional acoustic model predictions. µUS tools that can detect and measure microscopic changes in precancerous tissue using a mouse small bowel model with an oncogenic mutation was developed. µUS transducer was used to test the hypothesis that the intestinal tissue morphology of WT (wild type) and ApcMin/+ (adenomatous polyposis coli) diverges with progressing age intervals (60, 90 and 120 days) of mice. A high frequency ultrasound scanning system was designed and the experiments were performed ex vivo using a focused 45 MHz, f-# = 2.85, µUS transducer. The data collected by scanning was used to compute the backscatter coefficients (BSC) and acoustic impedance (Z) of WT and ApcMin/+ mice. The 2D and 3D ultrasound images showed that µUS detects polyps < 500 µm in the scan plane. The measured values of BSC and Z showed differences between normal and precancerous tissue. The differences detected in precancerous murine intestine and human tissue using µUS were correlated with high resolution 3D optical imaging. This novel approach may provide a powerful adjunct to screening endoscopy for improved identification and monitoring, allowing earlier treatment of otherwise undetectable lesions.

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Lee, Peter. "Scalable multi-parametric imaging of excitable tissue : cardiac imaging." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:a2594103-894b-4e1c-bdbb-43886f0d7fe0.

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The field of cardiac electrophysiological imaging has advanced tremendously in the past three decades with developments in fluorescent dyes, photodetectors, optical filters, illumination sources, computers and electronics. This thesis describes several scalable multi-parametric imaging systems and their application to cardiac tissue preparations at various levels of complexity. Using off-the-shelf components, single-camera multi-parametric optical mapping systems are described for various fluorescent dye combinations and single-element photodiode-based fibre-optic detection systems are described for drug-testing applications. The instruments described take advantage of modern voltage-sensitive dyes, multi-band optical filters and powerful light-emitting-diodes, from the ultraviolet to the red. The two electrophysiological parameters focused on were transmembrane voltage and the intracellular calcium concentration. Several voltage and calcium dye combinations were established, which produce no signal cross-talk. Furthermore, second- and third-generation voltage dyes were characterized in cardiac tissue, in vitro and in vivo. The developed systems were then applied to isolated Langendorff-perfused whole-hearts, in vivo whole-hearts, thin ventricular tissue-slices and human induced pluripotent stem cell-derived cardiac tissue. The interventions applied include accurately-timed electrical and mechanical local stimulation of the whole-heart to generate ectopic beats, cardiotoxic drugs and flash-photolysis of caged-compounds. With the high-throughput demands of drug discovery and testing, further development of scalable optical electrophysiological systems may prove critical in reducing attrition and costs. And for in vivo optical mapping, development of minimally-invasive and clinically-relevant optical systems will be essential in validating existing theories based on in vitro experiments and exploring cardiac function and behaviour with the heart intact in the organism.

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Killich, Markus. "Tissue Doppler imaging Erstellung von Referenzwerten für tissue velocity imaging, strain und strain rate beim Hund /." [S.l.] : [s.n.], 2006. http://edoc.ub.uni-muenchen.de/archive/00006708.

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Poland, Simon. "Techniques in deep imaging within biological tissue." Thesis, University of Strathclyde, 2006. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21651.

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This thesis is concerned with the development of low-cost and practical biological optical imaging and diagnosis systems that will allow the user to image and resolve structure deep into biological tissue without the need for physical dissection. Research within this thesis can be divided into two main sections, namely (a) the development of optically sectioning microscopy systems incorporating adaptive optics to compensate for system and specimen induced aberrations, and (b) as an example of biological tissue and disease, the development of dental imaging devices to detect and diagnose dental disease (caries). Section (a) The ability of confocal and multiphoton microscopy techniques to image optical sections deep within biological samples is a major advantage in biology. Unfortunately, as one images deeper within a sample, image degradation increases due to aberrations and scattering. In this investigation, operating a confocal microscope in reflection, a deformable membrane mirror (DMM) was used to counteract for sample aberrations within a closed feedback loop. By selecting various image properties (e. g. brightness, contrast or resolution), various optimisation algorithms were used to improve this property by altering the shape of the DMM and compensate for aberrations. Taking axial and lateral point spread functions (PSFs), the improvement of the system was monitored. The ability of the adaptive optic system to optimise to a particular axial PSF (PSF engineering) was also examined. The use of various algorithms with an adaptive element in a confocal system has been demonstrated to show significant improvement in the axial resolution and signal intensity. While global optimisation algorithms such as the genetic algorithm are more likely to find the global maximum in solution space in comparison to hillclimbing, it usually takes longer to achieve an optimum solution. Particular fitness parameters have shown promise in increasing the effectiveness of the algorithmic search routines. Optimising certain axial PSF components appears to have a detrimental effect on the lateral PSF and resolution. In the situation where the best axial and lateral resolution is required, optimising for intensity appears to show the best all round result. By adapting the axial fitness parameter program, it has been shown that particular desired axial PSF shapes can be reproduced within an aberrated sample. This does appear to have some limitations due to the relative power of the mirror (stroke). Section (b) Using optical techniques, physiological changes associated with the onset of disease in biological tissue can be detected. Taking dental tissue as an example of a highly scattering biological media, a computer model based upon commercially available software was used to theoretically reproduce experimental results taken using a fibre optical confocal system on dental tissue. From simulations, it has been shown that such a system could microscopically measure the optical properties of a caries lesion within dental enamel non-invasively. A system based on the use of structured light to penetrate and quantify early stage dental caries was presented as a possible aid to dentistry. Although the system was able to optically section the carious surface as well as detect inhomogeneities greater than 60μm deep into the tooth sample, more studies must be carried out to assess the limitations of the system. On a macroscopic scale, a cost effective system known as near-infrared Lateral Illumination (L. I.) (which is based on transillumination techniques) was presented. In a preliminary study involving 15 ex-in vivo adult pre-molars and molars at various stages of dental decay, L. I. was shown to be the most effective occlusal caries diagnosis system when compared to some techniques currently available and in development.

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Lapp, Sarah Julia. "Bioluminescence Imaging Strategies for Tissue Engineering Applications." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32338.

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In vitro differentiation of stem cells in biocompatible scaffolds in a bioreactor is a promising method for creating functional engineered tissue replacements suitable for implantation. Basic studies have shown that mechanical, chemical, and pharmaceutical stimuli enhance biological functionality of the replacement as often defined by parameters such as cell viability, gene expression, and protein accumulation. Most of the assays to evaluate these parameters require damage or destruction of the cell-scaffold construct. Therefore, these methods are not suitable for monitoring the development of a functional tissue replacement in a spatial and temporal manner prior to implantation. Bioluminescence imaging is a technique that has been utilized to monitor cell viability and gene expression in various in vivo applications. However, it has never been applied in an in vitro setting for the specific purpose of evaluating a cell-scaffold construct. This research describes the design of flow perfusion bioreactor system suitable for bioluminescence imaging. In the first experimental chapter, the system was tested using MC3T3-E1 cells transfected with a constitutive bioluminescent reporter. It was found that bioluminescence imaging was possible with this system. In the second experimental chapter, MC3T3-E1 cells transfected with BMP-2 linked bioluminescence reporter were cultured by flow perfusion for a period of 11 days. Bioluminescence was detectable from the cells starting at day 4, while peaking in intensity between days 7 and 9. Further, it was also found that bioluminescence occurred in distinct regions within the scaffold. These results indicate that these strategies may yield information not available with current assays.
Master of Science

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Unnersjö-Jess, David. "High-resolution imaging of kidney tissue samples." Licentiate thesis, KTH, Cellulär biofysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207577.

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The kidney is one of the most important and complex organs in the human body, filtering hundreds of litres of blood daily. Kidney disease is one of the fastest growing causes of death in the modern world, and this motivates extensive research for better understanding the function of the kidney in health and disease. Some of the most important cellular structures for blood filtration in the kidney are of very small dimensions (on the sub-200 nm scale), and thus electron microscopy has been the only method of choice to visualize these minute structures. In one study, we show for the first time that by combining optical clearing with STED microscopy, protein localizations in the slit diaphragm of the kidney, a structure around 75 nanometers in width, can now be resolved using light microscopy. In a second study, a novel sample preparation method, expansion microscopy, is utilized to physically expand kidney tissue samples. Expansion improves the effective resolution by a factor of 5, making it possible to resolve podocyte foot processes and the slit diaphragm using confocal microscopy. We also show that by combining expansion microscopy and STED microscopy, the effective resolution can be improved further. In a third study, influences on the development of the kidney were studied. There is substantial knowledge regarding what genes (growth factors, receptors etc.) are important for the normal morphogenesis of the kidney. Less is known regarding the physiology behind how paracrine factors are secreted and delivered in the developing kidney. By depleting calcium transients in explanted rat kidneys, we show that calcium is important for the branching morphogenesis of the ureteric tree. Further, the study shows that the calcium-dependent initiator of exocytosis, synaptotagmin, is expressed in the metanephric mesenchyme of the developing kidney, indicating that it could have a role in the secretion of paracrine growth factors, such as GDNF, to drive the branching.

QC 20170523

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Erich, Katrin [Verfasser], and Carsten [Akademischer Betreuer] Hopf. "Investigation of Cancerous Tissues by MALDI Mass Spectrometry Imaging - Imaging of proteolytic activity in frozen tissue and standardised on-tissue digestion / Katrin Erich ; Betreuer: Carsten Hopf." Heidelberg : Universitätsbibliothek Heidelberg, 2019. http://d-nb.info/1193252393/34.

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Sikdar, Siddhartha. "Ultrasonic imaging of flow-induced vibrations in tissue /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6100.

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Hoyt, Kenneth Leon Forsberg Flemming. "Spectral strain estimation techniques for tissue elasticity imaging /." Philadelphia, Pa. : Drexel University, 2005. http://dspace.library.drexel.edu/handle/1860/504.

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Hilton, Judy A. "An Acoustic Imaging System for Soft Tissue Stress." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/HiltonJA2005.pdf.

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13

Bálint, Péter Vince. "Ultrasound imaging in joint and soft tissue inflammation." Thesis, University of Glasgow, 2002. http://theses.gla.ac.uk/2266/.

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The use of ultrasound as an extended and more objective investigation performed as an extension of physical examination has a potential role in studying inflammation in different rheumatic diseases such as rheumatoid arthritis (RT) and spondylarthropathy (SpA). Rheumatoid arthritis is a chronic disease causing joint inflammation and destruction. Metacarpophalangeal (MCP) joint involvement is one of the earliest and most permanent signs of RA. US has been used to detect synovitis and erosions in MCP joints with high accuracy when compared to X-ray and magnetic resonance imaging (MRI). In RA joints, power Doppler has been used to detect increased blood flow as a potential sign of inflammation but grey-scale and power Doppler ultrasonography was not compared to another method to detect increased blood flow in MCP joints. After RA the next most common inflammatory group of diseases are the seronegative spondylarthropathies. In SpA joint inflammation and ankylosis occur in addition to periarticular enthesitis, which is one of the major hallmarks of the disease and has been poorly studied by ultrasonography. In order to reduce observer variation in musculoskeletal ultrasound examination to the level of other imaging methods it is necessary to avoid direct contact between the observer and the subject. This problem has been addressed in the aerospace industry and led to the development of air-coupled non-destructive testing. Air-coupled ultrasonography has the potential in medial imaging to exclude observer variation if it is able to depict human anatomy. There are currently no data regarding airborne ultrasound in the musculoskeletal ultrasound literature.

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Li, Teng. "Advanced Photoacoustic Measurement and Imaging in Biological Tissue." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506584.

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Tillberg, Paul W. "Expansion microscopy : improving imaging through uniform tissue expansion." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106094.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 70-76).
Until the past decade, optical microscopy of biological specimens was strongly limited by diffraction and scattering, affecting imaging resolution and depth, respectively. Now, numerous methods are available to overcome each of these limitations, but sub-diffraction limited resolution imaging over large volumes of scattering tissue is still a challenge. This work concerns the development of a new method, Expansion Microscopy (ExM) for achieving effect sub-diffraction-limited optical images in biological specimens. In ExM, the specimen is embedded in a swellable gel material to which fluorescent probes are chemically anchored. The embedded tissue is strongly digested so that it will not hinder uniform expansion driven by the gel. The gel with embedded, fragmented tissue is washed in water, triggering expansion of around 4-fold in each dimension. A variant of the method, ExM with Protein Retention (proExM) is presented that allows proteins themselves, rather than fluorescent probes, to be anchored by a small molecule cross-linker to the gel, so that the method may be carried out entirely with commercial components and standard antibodies.
by Paul W. Tillberg.
Ph. D.

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Hill, Esme. "Perfusion imaging and tissue biomarkers for colorectal cancer." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:4a309265-6f27-4839-9259-f19cf9648c2d.

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Background: Systemic chemotherapy and radiotherapy play an important role in the treatment of colorectal cancer. Tumour perfusion and oxygenation is known to influence radiosensitivity and chemosensitivity. In this thesis, I propose that the evaluation of changes in tumour perfusion using perfusion CT (pCT) and dynamic contrast-enhanced (Dce) MRI can guide the rational sequencing of drugs and radiation. Methods: Dce-MRI and pCT scans were incorporated into a clinical trial of hypofractionated pelvic radiotherapy and nelfinavir in 10 patients with rectal cancer. Toxicity and tissue biomarkers (tumour cell density, microvessel density, CAIX, HIF1-alpha, phospho-Akt and phospho-PRAS40) were evaluated. pCT liver scans were incorporated into an imaging study in patients with colorectal liver metastases randomised to receive either oxaliplatin/ 5FU chemotherapy or oxaliplatin/ 5FU chemotherapy plus selective internal radiotherapy. Results: After 7 days of nelfinavir concurrent with hypo-fractionated pelvic radiotherapy, there was a mean 42% increase in median K^trans (P=0.03, paired t test) on Dce-MRI and a median 30% increase in mean blood flow on pCT (P=0.028, Wilcoxon Rank Sum), although no statistically significant changes in perfusion parameters were demonstrated after 7 days of nelfinavir prior to radiotherapy. The feasibility of evaluating tumour cell density in rectal biopsies before and after radiotherapy and a radiosensitising drug as an early endpoint of response was demonstrated. In patients with colorectal liver metastases who received oxaliplatin and modified de Gramont chemotherapy alone, after 4 cycles of chemotherapy, a 28% decrease in the mean hepatic arterial fraction was observed (P=0.018, paired t test). Between pCT scans 2 days before SIRT and 39-47 days following SIRT and continued 2-weekly chemotherapy, there was a mean 62% (P=0.009) reduction in Blood Flow and 61% (P=0.006) reduction in Blood Volume (paired t test). Conclusions This research does not support the hypothesis that nelfinavir before radiotherapy improves blood flow to human rectal cancer. Increases in rectal tumour perfusion during radiotherapy and concurrent nelfinavir are likely to be primarily explained by the acute biological effects of radiation. Four or more cycles of oxaliplatin and modified de Gramont chemotherapy may result in changes in tumour perfusion of colorectal liver metastases which would be detrimental to subsequent radiotherapy. Selective internal radiotherapy resulted in substantial reductions in tumour perfusion 39-47 days after the treatment. Perfusion imaging can be used to detect changes in tumour perfusion in response to radiotherapy and systemic therapy which have implications for the sequencing of therapies.

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Laurens, Ediuska V. "Imaging of Tyramine-Substituted Hydrogels for Tissue Replacement." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1265639619.

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Penmatsa, Madhuri Krishna. "Infrared Spectral Imaging Analysis Of Cartilage Repair Tissue." Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/124100.

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Bioengineering
M.S.
Articular cartilage is a homogenous tissue that provides frictionless movement between joints while withstanding repetitive physical stress. Once degenerated as a result of osteoarthritis or an injury, it has very limited capacity for self-repair. Recent research has focused on developing many new technologies for cartilage repair. The successful application of these strategies is limited in part to lack of techniques to evaluate tissue response to interventions. Assessment of the structural and molecular changes in the primary cartilage components, proteoglycan (PG) and collagen is critical to evaluate progress of the repair tissue. In the present study Fourier transform infrared imaging spectroscopy (FT-IRIS) was utilized to evaluate molecular changes in normal and degenerated cartilage in a rabbit model of repair. Parameters such as collagen integrity, type II collagen and proteoglycan are important factors in determining the biomechanical properties of articular cartilage, and are likely as important in determining functional competence of repair tissue. Histological evaluations are considered to be one of the most important methods for determining the quality of the repair tissue, but still do not predict clinical outcome. It is possible that a new tissue scoring system that considers molecular parameters in the repair tissue, along with the histological outcomes, will better predict clinical success of repair. The main goal of this study is to assess correlations between histological grading, immunohistochemical assessments of type I and II collagen, and FT-IRIS parameters, in cartilage repair tissue in a rabbit model. These data will provide the basis for a novel tissue scoring system using FT-IRIS parameters alone, or in conjunction with histological and immunohistochemical outcomes. This could yield better correlations with clinical outcomes that may lead to optimization of the cartilage repair process.
Temple University--Theses

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Hui, Sai-kam, and 許世鑫. "Magnetic resonance diffusion tensor imaging for neural tissue characterization." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42841306.

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Ke, Meng-Tsen. "Optical clearing and deep-tissue fluorescence imaging using fructose." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188839.

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Roy, Ranadhir. "Image reconstruction from light measurements on biological tissue." Thesis, University of Hertfordshire, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338567.

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Hofstad, Erlend Fagertun. "Ultrasound Contrast Imaging - Improved Tissue Suppression in Amplitude Modulation." Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9316.

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The ability to image myocardial perfusion is very important in order to detect coronary diseases. GE Vingmed Ultrasound uses contrast agent in combination with a pulse inversion (PI) technique to do the imaging. But this technique does not function sufficiently for all patients. Therefore have other techniques been tested out, including transmission of pulses with different amplitude (AM), to enhance the nonlinear signal from contrast bubbles. But a problem achieving sufficient cancellation of linear tissue signal is a feebleness of the method. In this diploma work has an effort been put into enhancing the tissue suppression in amplitude modulation. First the source of the lack of suppression was searched for by measuring electrical and acoustical pulses. The further examination revealed a dissymmetry in between pulses of different amplitude. To reduce this error were several attempts to make a compensation filter performed, which finally resulted in a filter created of echo data acquired from a tissue mimicking phantom. The filter was furthermore tested out on a flow phantom to see how it affected the signal from tissue and contrast bubbles, compared to the former use of a constant instead of the filter. The comparison showed 1.5-3.2 dB increase in tissue suppression (TS). But unfortunately did the filtering process slightly reduce the contrast signal as well, which resulted in a smaller increase of Contrast-to-Tissue-Ratio (CTR) than TS; 1.0-2.8 dB. During the work was the source of another problem concerning tissue suppression discovered. In earlier work by the author cite{prosjekt} the experimental results suffered from low TS around the transmitted frequency, which was found inexplicable at that time. This problem was revealed to be caused by reverberations from one pulse, interfering with the echoes from the next pulse. The solution suggested in this thesis is to transmit pulses in such a way that every pulse used to create an image has a relatively equal pulse in front. For instance, if a technique employs two pulses to create an image, and the first has half the amplitude and opposite polarity of the second. Then, to eliminate the reverberations must the first imaging pulse have a pulse in front which has half the amplitude and opposite polarity of the pulse in front of the second imaging pulse.

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Walker, Paul Michael. "A test material for tissue characterization in N.M.R. imaging." Thesis, Imperial College London, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338275.

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Utting, Jane Francis. "Magnetic resonance imaging of tissue microcirculation in experimental studies." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272348.

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Winder, Robert John. "Medical imaging : tissue volume measurement & medical rapid prototyping." Thesis, University of Ulster, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399689.

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Hui, Sai-kam. "Magnetic resonance diffusion tensor imaging for neural tissue characterization." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42841306.

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Lee, Z. S. "Towards real-time imaging of strain in soft tissue." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/20003/.

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Meeus, Emma Maria. "Investigation of tissue microenvironments using diffusion magnetic resonance imaging." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8372/.

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Diffusion-weighted magnetic resonance imaging (DW-MRI) has rapidly become an important part of cancer patient management. In this thesis, challenges in the analysis and interpretation ofDW-MRI data are investigated with focus on the intravoxel incoherent motion (IVIM) model, and its applications to childhood cancers. Using guidelines for validation of potential imaging biomarkers, technical and biological investigation of IVIM was undertaken using a combination of model simulations and in vivo data. To reduce the translational gap between the research and clinical use of IVIM, the model was implemented into an in-house built clinical decision support system. Technical validation was performed with assessment of accuracy, precision and bias of the estimated IVIM parameters. Best performance was achieved with a constrained IVIM fitting approach. The optimal use of b-values was dependent on the tissue characteristics and a compromise between bias and variability. Reliable data analysis was strongly dependent on the data quality and particularly the signal-to-noise ratio. IVIM perfusion fraction (j) was generally found to correlate with dynamic susceptibility contrast imaging derived cerebral blood volume. IVIM-f also presented as a potential diagnostic biomarker in discriminating between malignant retroperitoneal tumour types. Overall, the results encourage the use of IVIM parameters as potential imaging biomarkers.

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Zhang, Yu. "Hyaluronan Based Biomaterials with Imaging Capacity for Tissue Engineering." Doctoral thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300799.

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This thesis presents the preparation of hyaluronan-based biomaterials with imaging capability and their application as scaffolds in tissue engineering. First, we have synthesized HA derivatives functionalized with different chemoselective groups. Then, functional ligands with capacities for hydrophobic drug loading, imaging, and metal ion coordination were chemically conjugated to HA by chemoselective reactions with these groups. An injectable in situ forming HA hydrogel was prepared by hydrazone cross-linking between hybrid iron-oxide nanogel and HA-aldehyde (paper-I). The degradation of this hydrogel could be monitored by MRI and UV-vis spectroscopy since it contained iron oxide as a contrast agent and pyrene as a fluorescent probe. Additionally, this hydrogel has a potential for a delivery of hydrophobic drugs due to its pyrene hydrophobic domains. The degradation study showed that degradability of the hydrogel was correlated with its structure. Based on the obtained results, disulfide cross-linked and fluorescently labeled hydrogels with different HA concentration were established as a model to study the relationship between the structure of the hydrogel and its degradability (paper-II). We demonstrated that disulfide cross-linked HA hydrogel could be tracked non-invasively by fluorescence imaging. It was proved that the in vivo degradation behavior of the hydrogel is predictable basing on its in vitro degradation study. In paper-III, we developed a disulfide cross-linked HA hydrogel for three-dimensional (3D) cell culture. In order to improve cell viability and adhesion to the matrix, HA derivatives were cross-linked in the presence of fibrinogen undergoing polymerization upon the action of thrombin. It led to the formation of an interpenetrating double network (IPN) of HA and fibrin. The results of 3D cell culture experiments revealed that the IPN hydrogel provides the cells with a more stable environment for proliferation. The results of the cellular studies were also supported by in vitro degradation of IPN monitored by fluorescence measurements of the degraded products. In paper-IV, the effect of biomineralization on hydrogel degradation was evaluated in a non-invasive manner in vitro. For this purpose, two types of fluorescently labeled hydrogels with the different ability for biomineralization were prepared. Fluorescence spectroscopy was applied to monitor degradation of the hydrogels in vitro under two different conditions in longitudinal studies. Under the supply of Ca2+ ions, the BP-modified hydrogel showed the tendency to bio-mineralization and reduction of the rate of degradation. Altogether, the performed studies showed the importance of imaging of hydrogel biomaterials in the design of optimized scaffolds for tissue engineering.

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Zhao, Mingjun. "NONINVASIVE MULTIMODAL DIFFUSE OPTICAL IMAGING OF VULNERABLE TISSUE HEMODYNAMICS." UKnowledge, 2019. https://uknowledge.uky.edu/cbme_etds/58.

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Measurement of tissue hemodynamics provides vital information for the assessment of tissue viability. This thesis reports three noninvasive near-infrared diffuse optical systems for spectroscopic measurements and tomographic imaging of tissue hemodynamics in vulnerable tissues with the goal of disease diagnosis and treatment monitoring. A hybrid near-infrared spectroscopy/diffuse correlation spectroscopy (NIRS/DCS) instrument with a contact fiber-optic probe was developed and utilized for simultaneous and continuous monitoring of blood flow (BF), blood oxygenation, and oxidative metabolism in exercising gastrocnemius. Results measured by the hybrid NIRS/DCS instrument in 37 subjects (mean age: 67 ± 6) indicated that vitamin D supplement plus aerobic training improved muscle metabolic function in older population. To reduce the interference and potential infection risk on vulnerable tissues caused by the contact measurement, a noncontact diffuse correlation spectroscopy/tomography (ncDCS/ncDCT) system was then developed. The ncDCS/ncDCT system employed optical lenses to project limited numbers of sources and detectors on the tissue surface. A motor-driven noncontact probe scanned over a region of interest to collect boundary data for three dimensional (3D) tomographic imaging of blood flow distribution. The ncDCS was tested for BF measurements in mastectomy skin flaps. Nineteen (19) patients underwent mastectomy and implant-based breast reconstruction were measured before and immediately after mastectomy. The BF index after mastectomy in each patient was normalized to its baseline value before surgery to get relative BF (rBF). Since rBF values in the patients with necrosis (n = 4) were significantly lower than those without necrosis (n = 15), rBF levels can be used to predict mastectomy skin flap necrosis. The ncDCT was tested for 3D imaging of BF distributions in chronic wounds of 5 patients. Spatial variations in BF contrasts over the wounded tissues were observed, indicating the capability of ncDCT in detecting tissue hemodynamic heterogeneities. To improve temporal/spatial resolution and avoid motion artifacts due to a long mechanical scanning of ncDCT, an electron-multiplying charge-coupled device based noncontact speckle contrast diffuse correlation tomography (scDCT) was developed. Validation of scDCT was done by imaging both high and low BF contrasts in tissue-like phantoms and human forearms. In a wound imaging study using scDCT, significant lower BF values were observed in the burned areas/volumes compared to surrounding normal tissues in two patients with burn. One limitation in this study was the potential influence of other unknown tissue optical properties such as tissue absorption coefficient (µa) on BF measurements. A new algorithm was then developed to extract both µa and BF using light intensities and speckle contrasts measured by scDCT at multiple source-detector distances. The new algorithm was validated using tissue-like liquid phantoms with varied values of µa and BF index. In-vivo validation and application of the innovative scDCT technique with the new algorithm is the subject of future work.

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Shukla, Vipul. "Intravital Imaging of Borrelia burgdorferi in Murine Skin Tissue." University of Toledo Health Science Campus / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=mco1271697663.

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32

Pašović, Mirza. "Tissue harmonic reduction : application to ultrasound contrast harmonic imaging." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10060.

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Les agents de contraste sont de petites bulles qui répondent non linéairement lorsqu’ils sont exposés à ultrasons. La réponse non-linéaire donne la possibilité d’images échographiques harmoniques qui a beaucoup d’avantages sur l’imagerie fondamentale. Toutefois, afin d’accroître l’échographie de contraste d’imagerie harmonique de performance nous devons d’abord comprendre la propagation non linéaire d’ultrasons. La non-linéarité du milieu déforme l’onde qui se propage, tels que les harmoniques commencent à se développer. La théorie qui a été prévue est la mise en œuvre, qui a permis une nouvelle méthode de modélisation de propagation des ultrasons non-linéaire. La connaissance acquise au cours de ce processus a été utilisée pour construire un deuxième signal à composantes multiples pour la réduction des harmoniques générées en raison des non-linéarités des tissus. En conséquence, la détection d’agents de contraste ultrasonore aux harmoniques a été augmentée. Une puissante technique d’imagerie échographique (Pulse inversion) a été renforcée avec le deuxième signal pour la réduction des harmoniques. Qu’est-ce qui a été appris pendant l’investigation : le pulse inversion technique a donné une nouvelle phase codée, appelée inversion de seconde harmonique. En outre, il a été noté que pour différents types de médias le niveau de distorsion de l’impulsion à ultrasons est différent. Cela dépend en grande partie du paramètre non linéaire B / A. Les travaux sur ce paramètre n’a pas été fini, mais il est quand même important de continuer dans cette direction puisque B / A imagerie avec des agents de contraste ultrasonore a beaucoup de potentiel
Ultrasound contrast agents are small micro bubbles that respond nonlinearly when exposed to ultrasound wave. The nonlinear response gives possibility of harmonic ultrasound images which has many advantages over fundamental imaging. However, to increase ultrasound contrast harmonic imaging performance we must first understand nonlinear propagation of ultrasound wave. Nonlinear propagation distorts the propagating wave such that higher harmonics appear as the wave is propagating. The theory that was laid down, was allowed implementing a new method of modelling nonlinear ultrasound propagation. The knowledge obtained during this process was used to construct a multiple component second harmonic reduction signal for reduction of their harmonics generated due to the tissue nonlinearities. As a consequence detection of ultrasound contrast agents at higher harmonics was increased. Further more, a powerful ultrasound imaging technique called Pulse Inversion, was further enhanced with multiple component second harmonic reduction signal. What was learned during investigation of the Pulse Inversion, technique lead to a new phase coded ultrasound contrast harmonic method called second harmonic inversion;. Also it was noted that for different type of media the level of distortion of ultrasound pulse is different. It depends largely on the nonlinear parameter B / A. Although the work on this parameter has not been finished it is very important to continue in this direction since B / A imaging with ultrasound contrast agents has a lot of potential

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33

Hofmann, Matthias Colin. "Localized Excitation Fluorescence Imaging (LEFI)." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/27749.

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A major limitation in tissue engineering is the lack of nondestructive methods to assess the development of tissue scaffolds undergoing preconditioning in bioreactors. Due to significant optical scattering in most scaffolding materials, current microscope-based imaging methods cannot â seeâ through thick and optically opaque tissue constructs. To address this deficiency, we developed a scanning fiber imaging method capable of nondestructive imaging of fluorescently labeled cells through a thick and optically opaque vascular scaffold, contained in a bioreactor. This imaging modality is based on local excitation of fluorescent cells, acquisition of fluorescence through the scaffold, and fluorescence mapping based on the position of the excitation light. To evaluate the capability and accuracy of the imaging system, human endothelial cells, stably expressing green fluorescent protein (GFP), were imaged through a fibrous scaffold. Without sacrificing the scaffolds, we nondestructively visualized the distribution of GFP-labeled endothelial cells on the luminal surface through a ~500 Âµm thick tubular scaffold at cell-level resolutions and distinct localization. These results were similar to control images obtained using an optical microscope with direct line-of-sight access. Through a detailed quantitative analysis, we demonstrated that this method achieved a resolution of the order of 20-30 Âµm, with 10% or less deviation from standard optical microscopy. Furthermore, we demonstrated that the penetration depth of the imaging method exceeded that of confocal laser scanning microscopy by more than a factor of 2. Our imaging method also possesses a working distance (up to 8 cm) much longer than that of a standard confocal microscopy system, which can significantly facilitate bioreactor integration. This method will enable nondestructive monitoring of endothelial cells seeded on the lumen of a tissue-engineered vascular graft during preconditioning in vitro, as well as for other tissue-engineered constructs in the future.
Ph. D.

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Lai, Di. "Independent component analysis (ICA) applied to ultrasound image processing and tissue characterization /." Online version of thesis, 2009. http://hdl.handle.net/1850/11367.

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Zhang, Zhongping, and 张忠平. "Quantitative in vivo assessment of tissue microstructure using diffusion tensor and kurtosis imaging." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B4694395X.

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Shallof, Abulgasim M. "Multi-frequency electrical impedance tomography for medical diagnostic imaging." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265987.

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Cheung, Man-hin Matthrew, and 張文騫. "Development of diffusion and functional magnetic resonance imaging techniques for neuroscience." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47147635.

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Khojasteh-Lakelayeh, Mehrnoush. "Methods for improved imaging and analysis of tissue-based biomarkers." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43728.

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Study of molecular biomarkers can provide insight into the molecular complexity of cancer, create new cancer screening tools, monitor treatment’s effectiveness, and predict patient’s response to treatment. This thesis proposes novel methods for the improved quantitative analysis of labeled molecular biomarkers in tissue sections. This is a necessary step towards the ultimate goal of personalized treatment of cancer. As 85% of all cancers arise in epithelial tissue, we have developed means for objectively and quantitatively assessing the distribution of a molecular biomarker in epithelial tissue sections. We have applied this means to characterize the spatial distribution of proliferating cells in 613 normal and pre-neoplastic bronchial epithelial biopsies. We have demonstrated, for the first time ever, that the knowledge of the spatial distribution of proliferating cells enables prediction of the outcome of lung intraepithelial lesions. We have developed methods for the automated and quantitative assessment of the expression of tissue-based molecular biomarkers on a cell-by-cell basis. This is achieved by multispectral imaging of labeled tissue sections. We have proposed methods for unsupervised linear spectral unmixing of multispectral images for the purpose of identifying individual labels in a multiple labeled tissue section. We have demonstrated that the use of multispectral imaging combined with our proposed analysis methods quantitatively improves the results of cell nuclei identification compared to three-color RGB imaging, in more than 22,000 cells in 58 tissue sections with nuclear, cytoplasmic, or membrane bound biomarkers. Finally, we have developed an imaging method for capturing images representing biomarkers in a tissue. Compared to multispectral imaging, our proposed imaging method significantly reduces the number of captured images required for the identification of a biomarker in a tissue. This method uses images captured under a series of narrow-band illumination spectra φ_i,i=1,2,…,N to find a weighted linear combination of the images that represents a certain component in a tissue. The weights in the weighted linear combination of images are then used to design one or two illumination spectra as weighted linear combinations of the narrow-band spectra φ_i. Images representing the component of interest are then captured under the designed illuminations.

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Richter, Katrin. "Application of imaging TOF-SIMS in cell and tissue research /." Göteborg : Institute of Biomedicine, The Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/7447.

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Bonnema, Garret. "Imaging Tissue Engineered Blood Vessel Mimics with Optical Coherence Tomography." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194969.

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Optical coherence tomography (OCT) is a technology that enables 2D cross-sectional images of tissue microstructure. This interferometric technique provides resolutions of approximately 10-20 um with a penetration depth of 1-2 mm in highly scattering tissues. With the use of fiber optics, OCT systems have been developed for intravascular imaging with a demonstrated improvement in both resolution and dynamic range compared to commercial intravascular ultrasound systems. OCT studies of normal, atherosclerotic, and stented arteries indicate the ability of OCT to visualize arterial structures. These results suggest OCT may be a valuable tool for studying luminal structures in tissue engineered constructs.In the present study, new endoscopic OCT systems and analysis techniques were developed to visualize the growth and response of the cellular lining within a tissue engineered blood vessel mimic (BVM). The BVM consists of two primary components. A biocompatible polymeric scaffold is used to form the tubular structure. Human microvessel cells from adipose tissue are sodded on to the inner surface of the scaffold. These constructs are then developed and imaged within a sterile bioreactor.Three specific aims were defined for the present study. First, an OCT longitudinal scanning endoscope was developed. With this endoscope, a study of 16 BVMs was performed comparing images from OCT and corresponding histological sections. The study demonstrated that endoscopic imaging did not visually damage the mimic cellular lining. OCT images showed excellent correlation with corresponding histologicalsections. Second, a concentric three element endoscope was developed to provide radial cross-sections of the BVM. OCT images using this endoscope monitored lining development on three types of polymeric scaffolds. In the third specific aim, automated algorithms were developed to assess the percent cellular coverage of a stent using volumetric OCT images.The results of the present study suggest that OCT endoscopic systems may be a valuable tool for assessing and optimizing the development of tissue engineered constructs. Conversely, the BVMs modeled the arterial response to deployed stents allowing the development of automated OCT analysis software. These results suggest that blood vessel mimics may be used to advance OCT technology and techniques.

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41

He, Taigang. "Magnetic resonance imaging relaxometry for myocardial tissue characterisation in thalassemia." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521112.

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42

Zhu, Hui. "Scatterer number density estimation for tissue characterization in ultrasound imaging /." Online version of thesis, 1990. http://hdl.handle.net/1850/10882.

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43

Casasnovas, Ortega Nicole. "Developing osteoarthritis treatments through cartilage tissue engineering and molecular imaging." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76172.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Biological Engineering, 2012.
Cataloged from PDF version of thesis. Page 104 blank.
Includes bibliographical references.
Tissue engineering can be applied to develop therapeutic techniques for osteoarthritis, a degenerative disease caused by the progressive deterioration of cartilage in joints. An inherent goal in developing cartilage-replacement treatments is ensuring that tissue-engineered constructs possess the same properties as native cartilage tissue. Biochemical assays and imaging techniques can be used to study some of the main components of cartilage and assess the value of potential therapies. Agarose and self-assembling peptides have been used to make hydrogels for in vitro culture of bovine bone marrow stromal cells (BMSCs) which can differentiate into chondrocytes, undergo chondrogenesis, and produce cartilage tissue. So far, differences in cell morphology that characterize chondrogenesis had been observed in peptide hydrogels like KLD and RAD but not in the 2.0% agarose hydrogels typically used for culture. A tissue engineering study was conducted to determine if a suitable environment for cell proliferation and differentiation could be obtained using different agarose compositions. BMSCs were cultured in 0.5%, 1.0%, and 2.0% agarose hydrogels for 21 days following TGF-p1 supplementation. Results indicate that the 0.5% agarose hydrogels are clearly inferior scaffolds when compared to the 1.0% and 2.0% agarose hydrogels, which are generally comparable. Since agarose gels appear to be suboptimal in promoting chondrogenesis, self-assembling peptides should be used in future studies. In addition to the biochemical assays traditionally used in cartilage tissue engineering studies, atomic force microscopy (AFM) can be used to image aggrecan, one of the main components of cartilage. Imaging studies were carried out using fetal bovine epiphyseal aggrecan to optimize previous extraction and sample preparation procedures, as well as an AFM imaging protocol, for samples containing aggrecan. Experiments were conducted with 10, 25, and 50 ptg/mL aggrecan solutions to find the minimum concentration needed to create aggrecan monolayers on APTES-mica that would yield acceptable AFM images (25 [mu]g/mL). AFM instrument and software parameters were optimized to find the working range of the integral and proportional gains (0.2 - 0.4 and 0.6 - 0.8, respectively) and to increase the resolution, showing fields at the 800 nm level. Finally, an image processing protocol relevant to these molecules was established.
by Nicole Casasnovas Ortega.
S.M.

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44

Chen, Zhaomin. "Imaging Infrared Microscope Analysis of Fixation-free Liver Tumor Tissue." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1367421889.

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Woods, Stephan M. "VIBRATIONAL SPECTROSCOPY AND SPECTROSCOPIC IMAGING OF BIOLOGICAL CELLS AND TISSUE." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1322540287.

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46

Hamilton, Jason S. "Disease Tissue Imaging and Single Cell Analysis with Mass Spectrometry." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc984137/.

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Cells have been found to have an inherent heterogeneity that has led to an increase in the development of single-cell analysis methods to characterize the extent of heterogeneity that can be found in seemingly identical cells. With an understanding of normal cellular variability, the identification of disease induced cellular changes, known as biomarkers, may become more apparent and readily detectable. Biomarker discovery in single-cells is challenging and needs to focus on molecules that are abundant in cells. Lipids are widely abundant in cells and play active roles in cellular signaling, energy metabolism, and are the main component of cellular membranes. The regulation of lipid metabolism is often disrupted or lost during disease progression, especially in cancer, making them ideal candidates as biomarkers. Challenges exist in the analysis of lipids beyond those of single-cell analysis. Lipid extraction solvents must be compatible with the lipid or lipids of interest. Many lipids are isobaric making mass spectrometry analysis difficult without separations. Single-cell extractions using nanomanipulation coupled to mass spectrometry has shown to be an excellent method for lipid analysis of tissues and cell cultures. Extraction solvents are tunable for specific lipid classes, nanomanipulation prevents damage to neighboring cells, and lipid separations are possible through phase dispersion. The most important aspect of single-cell analysis is that it uncovers the extent of cellular heterogeneity that exists among cellular populations that remains undetected during averaged sampling.

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Schneider, Caitlin Marie. "Ultrasound elastography for intra-operative use and renal tissue imaging." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61246.

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The kidney is a vital organ within the human body and improvements in the ability to characterize the kidney tissue can create benefits for patients with kidney tumors and for kidney transplant recipients. Often, changes in tissue health or development of cancer are manifested in changes in tissue structure that affect tissue elastic properties. For example, the cancerous tissue of renal cell carcinoma is stiffer than healthy kidney tissue, and the development of fibrosis, which impairs kidney function, also causes the tissue to become stiffer over time. These changes can be imaged with ultrasound elastography, a technique for quantitatively assessing tissue elasticity. If proven effective, elastography tissue characterization can replace biopsy. The ultrasound elastography method used in this thesis, called Shear Wave Absolute Vibro-Elastography, or SWAVE, measures the wavelength of induced steady-state multi-frequency mechanical shear waves to calculate tissue elasticity. SWAVE can employ standard ultrasound transducers that image the kidney though the skin above the organ, or custom miniaturized transducers that are placed directly on the surface of the organ during surgery. The accuracy of SWAVE is vastly improved by the use of 3D ultrasound data. We propose and evaluate 3D SWAVE imaging based on the use of a tracked intra-operative ultrasound transducer designed for use with the da Vinci Robot. Different tracking methods are evaluated for future intra-operative use. Elasticity images of tissue phantoms are obtained using interpolated 3D tissue displacement data acquired with the da Vinci robot and the intra-operative transducer. The use of tracked ultrasound transducer opens the way for introducing registered preoperative imaging, including elastography, to improve surgical guidance. Different methods of characterizing kidney tissue using SWAVE imaging are examined. The elastic and viscous properties are estimated kidney tissue ex-vivo. The effect of arterial pressure on the measured kidney elasticity is characterized. It was found that increasing input pressure increases the measured elasticity. Finally, ultrasound and ultrasound elastography are applied to kidney transplant recipients in-vivo to assess the level of fibrosis development. A preliminary study indicates that it is possible to transmit shear waves into the transplanted kidney and measure the elastic properties of the kidney tissue.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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Murphy, Richard James. "Development of tissue and imaging biomarkers of rotator cuff tendinopathy." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:b63377cb-b569-41dc-a3a8-099743dd66d3.

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Rotator cuff tendinopathy accounts for the majority of cases of shoulder pain, however, the aetiology and pathophysiology of the condition is poorly understood and treatment interventions for the condition have been introduced on an empirical basis, guided only by unproven theories of biological and structural changes in and around the affected tissue. This thesis explores changes in the provision of surgical interventions for rotator cuff tendinopathy, showing a rapid, sustained increase over the last decade. Investigation into the use of ultrasound as a clinical and research tool led to the development of an independent learning method for surgeons using the modality for shoulder imaging and highlighted the technological limitations of contrast enhanced ultrasound in assessing the microvascularity of the supraspinatus tendon. Development of a novel biopsy method for sampling the supraspinatus tendon permitted collection of tissue samples from several cohorts of individuals with rotator cuff tendinopathy. These studies, for the first time, described tissue changes across the whole spectrum of pathology suggesting the possibility of an early inflammatory phase of the condition followed by tissue senescence and reduced viability as pathology progressed. Paired samples taken before and after treatment identified reduced tissue activity in response to glucocorticoid therapy and a potential healing response from the supraspinatus tendon following surgical repair. Significant deterioration in tissue activity and viability was shown as age increased in a large cohort of individuals, highlighting the major impact of ageing as a factor in the onset and progression of rotator cuff tendinopathy. The techniques introduced provide standardised, reproducible methods for further evaluation of rotator cuff tendinopathy and the development of novel therapeutic interventions.

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Tadrous, Paul Joseph. "The imaging of benign and malignant breast tissue by flourescence lifetime imaging and optical coherence tomography." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407233.

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Bossart, Elizabeth L. "Magnetic resonance imaging and spectroscopy for the study of translational diffusion applications to nervous tissue /." [Florida] : State University System of Florida, 1999. http://etd.fcla.edu/etd/uf/1999/amj9926/bossart.pdf.

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Thesis (Ph. D.)--University of Florida, 1999.
Title from first page of PDF file. Document formatted into pages; contains xiv, 137 p.; also contains graphics. Vita. Includes bibliographical references (p. 129-136).

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Dissertations / Theses on the topic 'Tissue imaging'

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