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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Microcomputer control of a three-dimensional stereoflouroscope

Ellis, John Wesley 12 June 2010 (has links)
A microcomputer controller has been developed to operate a stereofluoroscopic system that is to be built at Virginia Polytechnic Institute and State University. The purpose of the controller is to provide the radiologist with the maximum amount of fluoroscopic information with the minimum amount of radiation exposure. The enhancement of the fluoroscopic information has been brought about through the implementation of real-time stereoscopic visualization. Stereoscopic visualization has been achieved by using PLZT crystal technology. The computer will control two grid-pulsed x-ray sources, an image intensifier, a solid-state video camera, a video monitor and the PLZT goggles to provide a stereoscopic image. Dose reduction should be obtained through the use of the computer as the controlling mechanism. Two storage tubes will be synchronized with the fluoroscopic apparatus to allow repeated replay of an instantaneous fluoroscopic image. A wide range of update rates can be selected by the radiologist to yield maximum radiation exposure savings. This stereofluoroscope is expected to provide real-time analysis with radiation exposures less than or equal to those achieved in conventional two-dimensional fluoroscopic analyses. / Master of Science
132

Optimizing diagnostic imaging through skills mix: costs and opportunities

McIntosh, Bryan 10 May 2017 (has links)
Yes / Increasing diagnostic capacity is a national priority to expedite the timeliness and appropriateness of patient treatment interventions. Imaging, encompassing a range of technologies including X-ray, Computer Tomography, Magnetic Resonance Imaging and ultrasound, is a key diagnostic service and central to decision making in most, if not all, disease pathways. However, imaging is an expensive discipline accounting for an estimated 3-5% of the annual NHS budget. As a result, it is imperative that we maximize service efficiency while optimizing patient outcomes.
133

Investigation in to the Effect of Spin Locking on Contrast Agent Relaxivity

Haigh, Julian Saunders 12 August 2015 (has links)
The current trend in magnetic resonance imaging (MRI) is towards higher external magnetic field strengths (B0) to take advantage of increased sensitivity and signal to noise ratio (SNR). Unfortunately, as (B0) increases the effectiveness (relaxivity) of clinical gadolinium (Gd3+)-based contrast agents (CAs) administered to enhance image contrast is significantly reduced. Excellent soft tissue contrast can be generated with current agents despite their non-optimum relaxivities but necessitates large doses. The limits of detection of a CA at high B0 fields can be lowered by recovering the lost relaxivity and is a pre-requisite to the goal of molecular imaging in which CAs are bound to biomarkers of pathology that exist at very low concentrations. Traditional methods for increasing the detectability of CAs have focused on optimizing critical parameters identified from the Solomon-Bloembergen-Morgan (SBM) theory that affect relaxivity. Gains in relaxivity with these methods to date have been modest and are far from the theoretical maximum possible. Although researchers continue to investigate novel complexes that provide improved relaxivities, any such complex would require a lengthy and costly approval process with the U.S. Food and Drug Administration (FDA). Therefore, a method that affords improved relaxivities of current clinically approved CAs, particularly at high B0 fields, that could be adopted into clinical practice rapidly, is of great interest. Spin locking is a nuclear magnetic resonance (NMR) technique that was introduced for imaging in 1985, but has received very little attention in combination with Gd3+-based CAs. The technique employs a low power long duration radiofrequency (RF) pulse (B1) parallel to the net magnetization in the x,y-plane. This locks the magnetization into lower precessional frequencies around an "effective" field (Beff) that is reduced with respect to B0 but maintains the high field advantages required for imaging. When considered in the rotating frame, longitudinal relaxation of the magnetization against Beff exhibits shorter time constants (T1p) expected at these lower precessional frequencies. This leads to higher relaxivities, which has implications for increasing CA detectability. The experiments described herein show that rotating frame longitudinal relaxivities (r1p) for current clinical Gd3+-based CAs are essentially independent of the strength of the spin lock pulse (yB1) as predicted by theory. This result is important because it allows the value of yB1 to be neglected when comparing r1p of Gd3+-based CAs across several B0 fields. The magnetic field dependence of r1p for all clinical agents showed that relaxivity, lost by moving to higher fields, could be "recovered" and that r1p was sensitive to the rotational correlation time constant (TR) of the agent. Using high molecular weight Nanoassembled capsules (NACs) containing a Gd3+-based CA to probe this finding further, we were able to generate relaxivities at high field up to an order of magnitude greater than clinical agents at current imaging fields. These are beyond anything previously reported, or likely to be, with current techniques. Finally, we demonstrated that by spin locking Mn2+ agents, relaxivities at high field increased by a factor of ~ 30 than without spin locking, due to their larger dependence on scalar coupling. These findings show the potential of spin locking to increase detection limits dramatically at high field and are an exciting development towards the goal of molecular imaging.
134

Middle cerebral artery (MCA) stenosis: genetic, pathological and imaging characterization. / CUHK electronic theses & dissertations collection

January 2006 (has links)
According to the literature, MRI has been applied to characterize the atherosclerosis in coronary and extracranial internal carotid artery. The cross-sections of MCA were scanned by Magnetic Resonance Imaging (MRI) to assess the accuracy of MRI in identifying MCA stenosis with histopathology as a golden standard, which was performed in the same post-mortem brains as in the second part. The sensitivity and specificity of MRI in detecting more than 30% MCA stenosis were 38.6% and 92.2%, with a positive predictive value of 87.2% and negative predictive value of 52.2%, and the corresponding values of MRI in identifying more than 50% MCA stenosis were 57.1%, 90.8%, 50% and 83.0%, respectively. Stenotic lesions >30% and >50% identified by MRI were found to be associated with infarctions in corresponding MCA territory. / After verification of potential relationship between ischemic stroke and intracranial artery calcification, the incidence of intracranial artery calcification was assessed in the ischemic stroke. One hundred and seventy-five ischemic stroke patients and 182 controls were enrolled. There was a higher prevalence of intracranial artery calcification in ischemic stroke patients than in controls. Hypertension, diabetes, smoking, intracranial artery calcification, hyperlipidemia, and atrial fibrillation were found to be independently associated with ischemic stroke. / Atherosclerotic stenosis is a heterogeneous disorder. The studies performed in extracranial carotid artery and coronary artery showed that the genes associated with lipoprotein metabolism may be associated with atherosclerosis. Thus, we speculated that the genes concerned with lipid metabolism may also be risk factors for MCA atherosclerotic stenosis. In the part of genetic analysis, clinical parameters and the genotypes of polymorphisms in the apolipoprotein E (ApoE), lipoprotein lipase (LPL), and paraoxonase (PON1) genes were compared in patients with and without MCA stenosis. Two hundred and ninety-four ischemic stroke patients were recruited, 136 cases with and 158 without MCA stenosis. Systolic blood pressure (SBP), rather than ApoE, LPL, and PON1 polymorphism was found to be a risk factor of MCA stenosis. / Calcification of intracranial artery, as a common complication of atherosclerosis, was investigated by multi-detector-row computed tomography (MDCT). By this advanced technique, the prevalence and location of calcification in intracranial arteries were determined, and its potential risk factors were also investigated. Four hundred and ninety patients were recruited. The incidence of intracranial artery calcification was 69.4%. The highest prevalence of intracranial artery calcification was seen in internal carotid artery (60%), followed by vertebral artery (20%), middle cerebral artery (5%) and basilar artery (5%). Age, a history of ischemic stroke, and white blood cell count were shown to be independently associated with intracranial artery calcification. / In the present study, genetic, pathological, imaging characterizations and prognosis of MCA stenosis were investigated. The effect of candidate genes has not been confirmed in the present study, but SBP and hypertension appears to contribute a lot to the occurrence of MCA stenosis among Chinese populations. As for the pathology of MCA atherosclerotic plaques, luminal stenosis and also the morphology of atherosclerotic plaque seem to play a cooperative role in leading to ischemic stroke. Imaging studies demonstrated the agreement between ex vivo MRI and histopathology in identifying MCA stenosis, and the correlation between the MCA stenosis identified by MRI and ischemic events. Calcification of intracranial artery, as a common complication of atherosclerosis, may be associated with age, history of ischemic stroke. High incidence of ischemic stroke has been demonstrated in Chinese type 2 diabetes patients. The presence of asymptomatic MCA stenosis plays an important role in the occurrence of ischemic stroke. / Lastly, using a cohort-study, we aimed to investigate stroke incidence of asymptomatic MCA stenosis and its risk factors in Chinese type II diabetic population. Transcranial Doppler was performed to define MCA stenosis. Incident strokes between 1996 and 2006 were ascertained by the database of Clinical Management System of the Hong Kong Hospital Authority. Anthropometric parameters (waist circumference and body mass index), blood pressure, and baseline plasma biochemical profile (lipid and glucose) were recorded to find the risk factors of ischemic stroke in asymptomatic MCA stenosis patients. Totally, 2,197 type II diabetic patients without symptoms of cerebrovascular disease were recruited. The evidence of MCA stenosis was identified in 272 subjects (12.4%), including 146 (53.7%) subjects with single-vessel involvement. Ischemic stroke occurred in one hundred and eighty-four (8.4%, 184/2197) patients. History of ischemic heart disease, MCA stenosis, the presence of retinopathy, lipid total cholesterol and age were independently associated with ischemic stroke. / Secondly, the pathological features of MCA stenosis and their relationship with cerebral infarcts were investigated in a series of post-mortem adults aged 45 years or above. The morphological features of the MCA atherosclerotic plaques were described in detail. The results demonstrated that the degree of luminal stenosis, the percentage of the plaques containing more than 40% lipid area, the values of cap-lipid, cap-lipid-stenosis, and the prevalence of intraplaque hemorrhage, neovasculature and thrombus were higher in the group of plaques associated with infarction. And the mean index of both CD45RO and CD68 were higher in the group of plaques associated with infarction. Binary logistic regression showed that stenosis, lipid area and presence of neovasculature were independent risk factors of MCA infarcts. / Stroke is one of the leading causes of death, disability, and dementia throughout the world. The stenosis of the intracranial large artery, especially the middle cerebral artery (MCA), is common in Chinese, Hispanic, and African populations. But MCA stenosis has been understudied due to its infrequency in the white population and its relative inaccessibility and invasiveness involved in its investigations. The purpose of the study was to investigate the genetic, pathological, imaging characteristics and prognosis of MCA atherosclerotic stenosis in Chinese population. / Chen Xiang-yan. / "September 2006." / Adviser: MH Ng. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1460. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 193-212). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
135

The utility of medical imaging in a novel infection: research based on severe acute respiratory syndrome (SARS). / CUHK electronic theses & dissertations collection

January 2005 (has links)
Background. Medical imaging has played an important role in the diagnosis, progress monitoring and follow-up of most disease entities, in particular chest infections. The emergence of a novel chest disease poses an immediate challenge to the pillars of imaging, namely chest radiography and computed tomography. The characteristic imaging appearances, differential diagnoses and diagnostic pitfalls need to be established for correct diagnosis and appropriate management. The sensitivity and utility of the different imaging modalities will also need to be addressed. / In the event of an outbreak or epidemic, these challenges are made more difficult by an overwhelming number of patients and limited resources. In March 2003, we were faced with such a situation in our institution and the disease was later termed Severe Acute Respiratory Syndrome (SARS). / Patients in Hong Kong were treated with a combination of an antiviral agent and corticosteroids in addition to respiratory support. The majority of patients improved with treatment, although between 20--36% required treatment in an intensive care unit. / Problems and importance. This novel disease of high infectivity, morbidity and mortality posed a major threat to public health and a challenge to health authorities both locally and internationally. With regard to medical imaging, the following research questions were identified: (1) What are the imaging signs of this new disease? (2) Does chest imaging provide a high degree of sensitivity for diagnosing the infection? (3) Are the imaging signs disease-specific or are they similar to other pathology? (4) Does the progressive evolution of the imaging appearance correlate with the clinical status of the patient? (5) Could the imaging appearance be useful for predicting the final outcome? (6) Are there complications that require detection by imaging? / The lung parenchyma is the main site of infection and the resultant microscopic pathology included: pulmonary exudate, sequestration of macrophages, diffuse alveolar damage, proliferation of epithelial cells and hyaline membrane formation. Macroscopic features include alveolar consolidation in the early stages and later, organizing pneumonia or bronchiolitis obliterans organizing pneumonia. / These answers to these questions are essential to our understanding of the disease and to increase our diagnostic ability. (Abstract shortened by UMI.) / This newly emerged disease is a respiratory infection with a high morbidity/mortality and was found to be caused by a coronavirus (SARS CoV). By the end of the outbreak a total of 8098 probable cases of infection were reported worldwide, with a mortality rate of 9.6% (774 deaths). Hong Kong was one of the hardest hit regions, totaling 1755 probable cases of infection and 299 deaths by the end of the outbreak. / Antonio Gregory Ernest. / "September 2005." / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3745. / Thesis (M.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 245-258). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.
136

Image segmentation using prior information and its application on medical ultrasound image processing. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Xie Jun. / "July 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 177-204). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
137

Variational and spline based multi-modal non-rigid medical image registration and applications. / CUHK electronic theses & dissertations collection

January 2005 (has links)
In the brain mapping case, the geodesic closest points are used as the anatomical constraints for the inter-subject non-rigid registration. The method uses the anatomical constraint in the non-rigid registration which is much more reasonable for the anatomical correspondence. The registration result shows significant improvement comparing with the iterative closest points based method. / In the third application, we use the non-rigid registration method to register the different sweeps of freehand ultrasound images. We setup a 3D freehand ultrasound imaging system to capture images of a human anatomy such as liver, prostate, brain tumor and fetus. The arbitrary scanned image slices are reconstructed and resliced into volumetric dataset. We use a B-spline based non-rigid registration method to compounding different freehand ultrasound sweeps. This technique can be used to make 3D ultrasound models of fetus and other organs. / Medical image registration is an active research area during the last two decades. The registration technique can be widely used in the applications of the computer aided surgery, brain mapping and pathological detection and analysis. With the development of the computing power, fast and accurate registration techniques have been developed into necessary tools for quantitative analysis of the medical image. / Non-rigid registration methods can be used in atlas based image segmentation, inter-subject brain image registration and 3D freehand ultrasound modeling. In one of our proposed novel segmentation methods, we interleave the segmentation and the registration processes by using the segmentation to provide the anatomical constraints for registration to improve the atlas based non-rigid registration. This updated registration can be used to improve the new segmentation. This process is repeated until a good result in segmentation is obtained. / The registration methods can be classified into rigid and non-rigid registrations according to whether the anatomy is locally deformed or not. According to the sensor by which the images are taken, the registration will be divided into mono-modal and multi-modal image registration. Since the invention of the medical imaging devices, great diversity of medical imaging sensors have been developed with different physical principles. In practice we have to face the problem of multi-modal registration. In medical image analysis, we often have to consider the images of the human anatomy with deformable characteristics. In order to achieve this goal we need to use the voxel based registration method which considers all of the voxel information of the images in matching. There are several non-rigid registration approaches. However, the variational approach of non-rigid registration can represent the registration problem into a well-posed problem with a well-founded mathematical base. In our work, we considered the forward and backward deformation functions and proposed a variational approach for a new consistent multi-modal non-rigid registration method. By this way, we will find the forward and backward transform to be close to the inverse of each other. This makes the correspondence between two images more consistent and accurate. We use both explicit and implicit difference method to solve the Euler-Lagrange equation and the results show significant improvements in the transformation inverse consistency. Although variational approach for multi-modal non-rigid registration can solve the non-rigid registration problem well, generally speaking, it is slow. The displacement of each voxel has to be calculated and the iteration time is very long since the number of the unknowns are large. Although a multi-resolution strategy can be used to speed up, the registration problem is still slow when registering large medical datasets. The 3D B-spline based method has been used as an efficient method to register medical images since only a small number of control points are used to manipulate the local deformation field. In our work, we developed a 3D B-spline based consistent multi-modal non-rigid registration method with an explicit representation of derivatives. The conventional optimization methods can be used to find the optimal parameters. We use a hierarchical B-spline refinement method to approximate the deformation function from larger to smaller scale. Since the derivatives of the cost function is represented in an explicit way, the computing is reduced. It is more efficient than directly computing the derivative of the cost function by using a numerical evaluation method. The method can be considered as a multi-grid method for solving the consistent variational registration problem. The computing speed is increased by several times. The B-spline based method needs far less iterations to converge as its number of unknowns is small. / Zhang Zhijun. / "October 2005." / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6645. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 209-233). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
138

Investigating biomedical applications with terahertz pulsed imaging in reflection geometry.

January 2011 (has links)
Sy, Ming Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (p. 95-100). / Abstracts in English and Chinese. / Abstract --- p.1 / Acknowledgments --- p.5 / List of figures --- p.9 / List of tables --- p.13 / List of abbreviations --- p.14 / List of publications and awards --- p.15 / Awards --- p.16 / Chapter Chapter 1 --- Introduction --- p.17 / Chapter 1.1 --- Terahertz radiation --- p.18 / Chapter 1.1.1 --- Terahertz sources --- p.19 / Chapter 1.1.2 --- Terahertz systems --- p.20 / Chapter 1.1.3 --- Reflection and Transmission geometries --- p.21 / Chapter 1.2 --- Terahertz biomedical applications --- p.24 / Chapter 1.2.1 --- Biomolecules --- p.24 / Chapter 1.2.2 --- THz biomedical imaging --- p.25 / Chapter 1.2.3 --- THz Spectroscopy --- p.26 / Chapter 1.3 --- Objectives --- p.26 / Chapter 1.4 --- Structure of this thesis --- p.26 / Chapter Chapter 2 --- Theory and experimental system --- p.28 / Chapter 2.1 --- Theory --- p.28 / Chapter 2.1.1 --- Propagation of electromagnetic field through dielectric media --- p.29 / Chapter 2.1.2 --- A de-noising method --- p.32 / Chapter 2.1.3 --- Baseline calculation --- p.34 / Chapter 2.1.4 --- Frequency-dependent Refractive Index and Absorption Coefficient.. --- p.37 / Chapter 2.2 --- Experimental Configuration --- p.41 / Chapter 2.2.1 --- Terahertz generation and detection --- p.41 / Chapter 2.2.2 --- Configuration of our system --- p.44 / Chapter 2.2.3 --- Hand-held TPI Setup --- p.46 / Chapter 2.3 --- Data Structure --- p.48 / Chapter 2.4 --- Pre-processing and the user interface --- p.49 / Chapter 2.4.1 --- Data pre-processing 1 (Chopping) --- p.49 / Chapter 2.4.2 --- Data pre-processing 2 (Angle selection) --- p.50 / Chapter 2.4.3 --- The user interface for the data processing --- p.52 / Chapter Chapter 3 --- Ex-v/vo experiment: investigating the origin of contrast --- p.54 / Chapter 3.1 --- Liver Cirrhosis --- p.54 / Chapter 3.1.1 --- Liver --- p.54 / Chapter 3.1.2 --- Liver cirrhosis --- p.54 / Chapter 3.1.3 --- The trend of liver cirrhosis --- p.56 / Chapter 3.1.4 --- Technique for diagnosing liver cirrhosis --- p.57 / Chapter 3.2 --- Experiment protocol --- p.58 / Chapter 3.2.1 --- Formalin fixing --- p.58 / Chapter 3.2.2 --- Sample preparation --- p.58 / Chapter 3.2.3 --- Formalin fixing protocol --- p.60 / Chapter 3.2.4 --- Histopathology --- p.61 / Chapter 3.2.5 --- Protocol for measuring sample water content --- p.61 / Chapter 3.3 --- Results and discussion --- p.62 / Chapter 3.3.1 --- Optical parameters of the fresh and fixed samples --- p.62 / Chapter 3.3.2 --- Consistency with previous results --- p.63 / Chapter 3.3.3 --- The relationship between water content and optical parameters --- p.64 / Chapter 3.3.4 --- Conclusion --- p.68 / Chapter Chapter 4 --- In-vivo experiment: imaging of human skin --- p.69 / Chapter 4.1 --- Human skin --- p.69 / Chapter 4.1.1 --- The structure of human skin --- p.69 / Chapter 4.1.2 --- Skin thickness --- p.70 / Chapter 4.1.3 --- The structure and regeneration of stratum corneum --- p.70 / Chapter 4.1.4 --- Stratum corneum related Skin disease --- p.72 / Chapter 4.2 --- Combing reflections of electromagnetic wave --- p.73 / Chapter 4.3 --- Experiment protocol --- p.74 / Chapter 4.3.1 --- THz response of human skin --- p.74 / Chapter 4.3.2 --- Protocol for measuring human skin --- p.75 / Chapter 4.4 --- Results and discussion --- p.76 / Chapter 4.4.1 --- The variation due to the position --- p.76 / Chapter 4.4.2 --- The variation due to the temperature and humidity --- p.78 / Chapter 4.4.3 --- Discussion --- p.79 / Chapter Chapter 5 --- Noise evaluation --- p.80 / Chapter 5.1 --- The main noise source --- p.80 / Chapter 5.2 --- SNR and DR --- p.80 / Chapter 5.2.1 --- Signal to noise ratio (SNR) --- p.80 / Chapter 5.2.2 --- Dynamic range (DR) --- p.81 / Chapter 5.2.3 --- SNRVS DR --- p.82 / Chapter 5.3 --- Simulation of noise impact on the complex refractive index --- p.83 / Chapter 5.3.1 --- Methodology --- p.83 / Chapter 5.3.2 --- SNR: Simulation results and discussions --- p.85 / Chapter 5.3.3 --- DR: Simulation results and discussions --- p.87 / Chapter 5.3.4 --- Conclusion --- p.89 / Chapter Chapter 6 --- Conclusion and future work --- p.90 / Chapter 6.1 --- Conclusion --- p.90 / Chapter 6.1.1 --- A summary of Terahertz pulsed imaging (TPI) techniques --- p.90 / Chapter 6.1.2 --- Our system and calculations --- p.90 / Chapter 6.1.3 --- Terahertz spectroscopy of liver cirrhosis: investigating the origin of contrast --- p.91 / Chapter 6.1.4 --- In-v/vo study: skin measurement --- p.91 / Chapter 6.1.5 --- SNR sensitivity --- p.92 / Chapter 6.2 --- Suggestions for future work --- p.92 / Chapter 6.2.1 --- Algorithms --- p.92 / Chapter 6.2.2 --- Understanding the origin of contrast --- p.93 / Chapter 6.2.3 --- Application in cardiovascular diagnosing imaging --- p.93 / Chapter 6.3 --- Concluding remarks --- p.94 / References --- p.95
139

Terahertz pulsed imaging of osteoarthritis joint cartilage.

January 2010 (has links)
Kan, Wai Chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (p. 111-116). / Abstract --- p.i / Acknowledgement --- p.iii / List of Publications --- p.vi / List of Figures --- p.xi / List of Tables --- p.xii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Terahertz Radiation --- p.1 / Chapter 1.2 --- Biomedical Applications of Terahertz Imaging --- p.3 / Chapter 1.3 --- THz Spectroscopy --- p.4 / Chapter 1.4 --- Osteoarthritis --- p.4 / Chapter 1.5 --- Aim and motivation --- p.5 / Chapter 1.6 --- Overview of thesis --- p.5 / Chapter 2 --- Theory --- p.7 / Chapter 2.1 --- Propagation of electromagnetic field through dielectric media --- p.7 / Chapter 2.2 --- Deconvolution --- p.10 / Chapter 2.3 --- Baseline offset --- p.12 / Chapter 2.4 --- Frequency-dependent Refractive Index and Absorption Coefficient --- p.15 / Chapter 2.4.1 --- Reflection Geometry --- p.15 / Chapter 2.4.2 --- Transmission Geometry --- p.17 / Chapter 2.5 --- Conversion of Optical Delay into Depth --- p.22 / Chapter 2.6 --- Finite Difference Time Domain Method --- p.23 / Chapter 2.7 --- Summary --- p.25 / Chapter 3 --- Terahertz Systems --- p.26 / Chapter 3.1 --- Terahertz Pulsed Generation --- p.26 / Chapter 3.2 --- Terahertz Pulsed Detection --- p.28 / Chapter 3.3 --- Terahertz Pulsed Imaging (TPI) System --- p.29 / Chapter 3.4 --- Reflection System --- p.29 / Chapter 3.4.1 --- Flatbed System --- p.29 / Chapter 3.4.2 --- Probe --- p.32 / Chapter 3.5 --- Transmission System --- p.36 / Chapter 3.5.1 --- Antenna --- p.39 / Chapter 3.6 --- Data Acquisition --- p.40 / Chapter 3.6.1 --- Flatbed System --- p.40 / Chapter 3.6.2 --- Probe --- p.42 / Chapter 3.7 --- Baseline Validation --- p.46 / Chapter 4 --- Osteoarthritis --- p.48 / Chapter 4.1 --- Introduction --- p.48 / Chapter 4.2 --- Cartilage Composition and Structure --- p.49 / Chapter 4.3 --- 〇A symptoms --- p.51 / Chapter 4.4 --- Other Imaging Techniques --- p.52 / Chapter 4.5 --- Sample Preparation and Histology --- p.54 / Chapter 5 --- THz Pulsed Imaging of OA --- p.58 / Chapter 5.1 --- Results --- p.58 / Chapter 5.1.1 --- Optical Delays --- p.59 / Chapter 5.1.2 --- Estimation of surface refractive index --- p.69 / Chapter 5.1.3 --- Conversion of Optical Delay into Cartilage Thickness --- p.72 / Chapter 5.1.4 --- Correlation with Histology --- p.74 / Chapter 5.1.5 --- Errors and Problems --- p.80 / Chapter 5.2 --- FDTD of cartilage layers --- p.85 / Chapter 5.3 --- Conclusion --- p.87 / Chapter 6 --- Sliced Cartilage Sample and Bone Measurement --- p.88 / Chapter 6.1 --- Sliced Cartilage Samples --- p.88 / Chapter 6.1.1 --- Multi-reflections of sliced cartilage samples --- p.89 / Chapter 6.1.2 --- The influence of pressure on cartilage thickness --- p.91 / Chapter 6.1.3 --- Estimation of surface refractive index of sliced cartilage samples --- p.93 / Chapter 6.1.4 --- Comparison between sliced cartilage and knee joint measurements --- p.95 / Chapter 6.2 --- Bone --- p.97 / Chapter 7 --- Transmission System Result --- p.99 / Chapter 7.1 --- Data Validation --- p.99 / Chapter 7.1.1 --- Water spectrum --- p.99 / Chapter 7.1.2 --- Quartz measurement --- p.100 / Chapter 7.2 --- Liquid cell --- p.100 / Chapter 7.3 --- Cartilage Transmission Result --- p.103 / Chapter 7.4 --- Difficulties and problems --- p.105 / Chapter 7.5 --- Conclusions --- p.106 / Chapter 8 --- Conclusions and future work --- p.107 / Chapter 8.1 --- Summary --- p.107 / Chapter 8.2 --- Discussion --- p.107 / Chapter 8.3 --- Suggestions for further study --- p.109 / Bibliography --- p.111
140

Hough transforms for shape identification and applications im medical image processing /

Lu, Wei, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 105-112). Also available on the Internet.

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