Student Theses -Optical Coherence Tomography News

Articles in category: Student Theses

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1. Planar and Integrated MEMS Micromirrors Based Endoscopic Optical Coherence Tomography (Thesis)
  
  Explore UFDC Home Sep 12 2016 Probes , Student Theses
  
  Optical coherence tomography (OCT) is a thriving imaging modality which provides high-resolution, in vivo, real-time, non-invasive, cross-sectional imaging capability for biomedical applications. Over the past decade, OCT has become a standard clinical diagnosis tool for ophthalmology. However, human organs other than eyeballs are all highly scattering tissues, which limits the OCT penetration depth to ~2 mm. Therefore, endoscopic OCT probes with small diameter must be developed for imaging internal organs. The key component of an endoscopic OCT probe is the optical scanner. Thus, the first objective of this work is to develop miniature optical scanners using microelectromechanical system (MEMS) technology ...
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  Mentions: University of Florida
2. High-definition optical coherence tomography: Contribution to the non-invasive near infrared optical imaging techniques of the skin (Thesis)
  
  Explore DI-fusion Recherche simple Jul 16 2016 Dermatology , Student Theses
  
  Background. The development of non-invasive imaging techniques has been stimulated by the shortcomings of histopathology. Currently the only valid diagnostic technique in dermatology is skin biopsy which remains a painful, invasive intervention for the patient. Moreover, this approach is not always convenient for monitoring and follow-up of a skin disease. Optical imaging technologies could solve these shortcomings as they are fast, precise, repeatable and painless. There are four established non-invasive skin imaging techniques used in daily practice: dermoscopy, high-frequency ultrasound, reflectance confocal microscopy (RCM) and conventional optical coherence tomography (C-OCT). In imaging there is a trade-off between resolution and penetration ...
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3. Share your OCT Thesis on OCT News
  
  Explore Optical Coherence Tomography News Jul 5 2016 Student Theses
  
  OCT News is seeking links to bachelors, masters, and PhD theses in the area of "Optical Coherence Tomography". Traditionally student theses contain a great wealth of information but are rarely accessible to the OCT community. If you or someone you know wrote an OCT thesis and would like to share it with the community please submit a link or PDF using the "Contact OCT News" tab in the main menu bar or the feedback link in the footer and we will include it here: Student Theses. Thesis will only be included if the link is free of charge to users.
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4. Swept Source Optical Coherence Tomography Imaging of the Middle Ear Cavity (Thesis)
  
  Explore IDEALS @ Illinois Jul 4 2016 Otolaryngology , Student Theses
  
  Otitis media (OM), a bacterial infection of the middle ear, is a common pediatric disease. Chronic and recurrent OM is often treated with the surgical placement of tympanostomy tubes in the tympanic membrane (TM), which is the most common reason for pediatric surgery and anesthesia. Antibiotic treatment for chronic OM (COM) is often ineffective, which is explained by the hypothesis that OM is a biofilm-related disease. Recent studies in humans and animals have accumulated evidence for biofilm growth on the middle ear mucosa in COM. However, these studies have required invasive methods to obtain middle ear mucosa samples. Optical Coherence ...
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  Mentions: Stephen A. Boppart University of Illinois at Urbana-Champaign
5. Development of Swept Source Optical Coherence Tomography and Adaptive Optics Scanning Laser Ophthalmoscopy: Improved Imaging Speed and Handheld Applications (Thesis)
  
  Explore DukeSpace at Duke University Jun 11 2016 Ophthalmology , Student Theses
  
  Optical coherence tomography (OCT) is a noninvasive three-dimensional interferometric imaging technique capable of achieving micrometer scale resolution. It is now a standard of care in ophthalmology, where it is used to improve the accuracy of early diagnosis, to better understand the source of pathophysiology, and to monitor disease progression and response to therapy. In particular, retinal imaging has been the most prevalent clinical application of OCT, but researchers and companies alike are developing OCT systems for cardiology, dermatology, dentistry, and many other medical and industrial applications. Adaptive optics (AO) is a technique used to reduce monochromatic aberrations in optical instruments ...
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  Mentions: Duke University
6. AUTOMATED MACHINE LEARNING BASED ANALYSIS OF INTRAVASCULAR OPTICAL COHERENCE TOMOGRAPHY IMAGES (Thesis)
  
  Explore OhioLINK ETD Center Jun 5 2016 Cardiology , Student Theses
  
  Coronary artery disease (CAD) is the leading cause of death in the world. Most acute coronary events (e.g. heart attacks) are due to the rupture of atherosclerotic plaques inside the arteries, however, calcified lesion is the most widely treatable, typically, by stent implantation via percutaneous coronary intervention (PCI). Intravascular Optical Coherence Tomography (IVOCT) imaging has the resolution, contrast, and penetration depth to characterize coronary artery plaques. Conventional manual evaluation of IVOCT images, based on qualitative interpretation of image features, is tedious and time consuming. The aim of this PhD dissertation was to develop advanced algorithms to fully automate the ...
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  Mentions: Case Western Reserve University
7. Attenuation Coefficients, Pixel Intensity, and Texture Analysis as Quantitative Parameters for Analyzing Optical Coherence Tomography Images of Vocal Fold Tissue (Thesis)
  
  Explore Digital Access to Scholarship at Harvard May 21 2016 Otolaryngology , Student Theses
  
  Optical coherence tomography is a promising technology to noninvasively assess vocal fold microanatomy. However, many studies using optical coherence tomography to evaluate vocal fold tissue are largely qualitative in nature and lack quantitative measures that might be useful in clinical decision-making. The goal of this thesis was to identify quantitative metrics that can be extracted from optical coherence tomography vocal fold imaging and applied to the surgical subspecialty of Laryngology. The first goal of this study was to determine if optical coherence tomography was sensitive enough to distinguish subtle differences between vocal folds based on vocal fold content using attenuation ...
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  Mentions: Harvard University
8. Optical coherence tomography Layout Simulation Using MATLAB®
  
  Explore Estudo Geral Apr 30 2016 Student Theses
  
  Optical Coherence Tomography (OCT) is a non-invasive optical imaging technique capable of producing 2D images or 3D reconstructions of nonhomogeneous samples. OCT is mainly used in ophthalmology as a powerful tool for the early diagnosis of ocular diseases. With OCT it is possible to obtain high resolution cross-sectional images of ocular structures, such as the retina or the anterior segment. An OCT platform for ocular image acquisition is being developed. It is based on a swept source laser, an InGaAs balanced detector, a data acquisition board installed on a personal computer, and several optical components. The main purpose of this ...
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  Mentions: University of Coimbra
9. Acoustic Radiation Force Optical Coherence Elastography : Localized Vs. Wide-Area Perturbation – A Comparison (Thesis)
  
  Explore Home Apr 21 2016 Student Theses
  
  Elastography is a method to image the biomechanical properties of tissues. The experimental setup has a 10 MHz ultrasound transducer (focal length of 5cm and a spot size of 0.3mm localized excitation and unfocused for wide-area excitation) which generates acoustic radiation force (ARF) to perturb the sample and the corresponding mechanical response is imaged with a spectral domain optical coherence tomography (SD-OCT) with a center wavelength of 800 nm and a bandwidth of 180 nm at a transverse optical resolution of 8[mu]m. The existing hypothesis which states that localized harmonic excitation in audio frequency regime has potential ...
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  Mentions: Cornell University
10. Advanced Monte Carlo Simulation and Machine Learning for Frequency Domain Optical Coherence Tomography
  
  Explore biblioteca.universia.net Mar 6 2016 Student Theses
  
  Optical Coherence Tomography(OCT) is a popular, rapidly growing imaging technique with an increasing number of bio-medical applications due to its noninvasive nature. However, there are three major challenges in understanding and improving an OCT system: (1) Obtaining an OCT image is not easy. It either takes a real medical experiment or requires days of computer simulation. Without much data, it is difficult to study the physical processes underlying OCT imaging of different objects simply because there aren't many imaged objects. (2) Interpretation of an OCT image is also hard. This challenge is more profound than it appears. For ...
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  Mentions: California Institute of Technology
11. Development of spectral domain optical coherence tomography for pharmaceutical and medical application
  
  Explore British Library EThOS Feb 1 2016 NDE/NDT , Student Theses
  
  Spectral-domain optical coherence tomography (SD-OCT) is a type of non-destructive imaging technique that is capable of resolving the inner structure of a sample with micrometre spatial resolution. SD-OCT is based on low coherence interferometry. It utilises a spectrometer to grab the spectral interferogram between the back reflected/scattered light from a reference mirror and a sample. The depth profile, which carries the sample inner structure information, is then generated by a data interpolation and Fourier Transform (FT). Functional coating of solid oral dosage forms optimises the release profile of active pharmaceutical ingredient (API) and results in a desirable API absorption ...
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12. Characterising the effect of a novel optical delay line and light sources on the resolvability of time domain optical coherence tomography (Thesis)
  
  Explore Edith Cowan University Jan 26 2016 Student Theses
  
  Optical coherence tomography (OCT) is a reflection based imaging technique, with numerous applications, initially in medical diagnostics. Unlike ultrasound, another reflection imaging technique, OCT relies on light scattering in samples, low coherence near- infrared interferometry, and graphical image construction, to acquire 2D and 3D reflectogram images. OCT has resolution an order of magnitude greater than ultrasound, but its depth penetration is less than a few millimetres. Axial resolution is a critical parameter in determining whether OCT can be used to resolve specific features in a sample image. Typically, measures of resolution have been attributed only to the light source’s ...
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13. Restoration of optical coherence tomography images using stochastic methods (Thesis)
  
  Explore MSpace Home Jan 22 2016 Student Theses
  
  Optical coherence tomography (OCT) is a rapidly growing imaging modality that produces high resolution three dimensional images that can be applied to different medical and industrial applications . Obtaining higher depth of imaging and higher imaging quality are important goals in OCT systems. One of the main factors that affects the penetration depth and imaging quality of OCT systems is the presence of noise. The depth-scan photocurrent of time domain (TD) OCT system is degraded by a class of correlated and signal dependent noise. The joint probability density function of the depth-scan photocurrent can be considered as Gaussian random process that ...
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  Mentions: University of Manitoba
14. Heartbeat Optical Coherence Tomography (Thesis)
  
  Explore repub.eur.nl Jan 21 2016 Cardiology , Student Theses
  
  Coronary artery disease (CAD) is a manifestation of atherosclerosis, a systemic inflammatory disease of the arteries that causes the formation of plaques in the artery walls. Different plaques may give rise to different symptoms: a gradual narrowing (stenosis) of the vessel by growth of a fibrous or calcific plaque will cause chest pain (due to cardiac ischemia) upon exertion, a condition called stable CAD. Sudden onset of chest pain, or chest pain at rest, is a symptom of unstable CAD or acute coronary syndrome (ACS), which is associated with thrombus formation on plaques, mostly due to rupture of a lipid-core ...
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  Mentions: Anton F. W. van der Steen Erasmus University Tianshi Wang
15. Development of a Retinal Eye Tracker for 3D Optical Coherence Tomography (Thesis)
  
  Explore TU Delft Institutional Repository Jan 20 2016 Ophthalmology , Student Theses
  
  Several eye diseases appear in the posterior part of the eye, i.e. the retina or fundus. Retinal images therefore provide valuable information to identify eye diseases. Optical Coherence Tomography (OCT) is a 3D imaging technique that can image the retina with a resolution and depth penetration that can not be achieved by any other non-invasive imaging technique. Although OCT can achieve high resolution, in vivo measurements are severely limited by eye motion. TNO developed a low-cost eye tracker with improved eye motion tracking compared to current state of the art eye trackers. The eye tracker images the retina at ...
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16. Ultra-widefield optical coherence tomography of the human retina (Thesis)
  
  Explore University of Glasgow Jan 7 2016 Ophthalmology , Student Theses
  
  Optical coherence tomography (OCT) has become a standard of care in ophthalmology since it was first demonstrated over 20 years ago. Images acquired using commercial OCT systems have been reported to have a maximum imaging length of only 9 mm, which is equivalent to an internal-field of view of 45◦. This narrow-field limitation has been acceptable because of the high level of clinical data available in the macular region and the relative simplicity of imaging this area of the retina. Commercially-available scanning laser ophthalmoloscope (SLO) systems such as the Optos 200Tx are capable of providing a fundus image with an ...
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  Mentions: Optovue Heidelberg Spectralis Optos
17. Evaluation of the Crystalline Lens Gradient Refractive Index using Laser Ray Tracing and Optical Coherence Tomography (Thesis)
  
  Explore Scholarly Repository Dec 23 2015 Ophthalmology , Student Theses
  
  $Evaluation of the Crystalline Lens Gradient Refractive Index using Laser Ray Tracing and Optical Coherence Tomography (Thesis)$
  The human crystalline lens is a complex and intricate structure that continuously grows throughout our lifetime. The crystalline lens has a non-uniform distribution of protein concentrations which produces an optical gradient within the lens in both the optical and equatorial axes. This gradient refractive index is a unique property of the crystalline lens that significantly contributes to its optical power and aberrations. The objective of this dissertation is to gain a better understanding of the relationship between the crystalline lens shape, its non-uniform gradient refractive index, the lens optical power and aberrations, and their changes with accommodation and age. The ...
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  Mentions: University of Miami Fabrice Manns Sonia H. Yoo
18. An Evaluation of Silicon Carbide Based Bimorph Actuators for Optical Coherence Tomography Applications
  
  Explore scholar.google.com Dec 1 2015 Student Theses
  
  Optical coherence tomography (OCT) probes rely on MEMS micro-scanners to provide fast and reproducible scans covering as much area as possible. A popular choice of actuators employed in this role are electrothermal bimorph actuators. They comprise of two layers of different materials which are rigidly joined together. Differential expansion under heating causes the bimorph to deflect. Polycrystalline silicon carbide has been proposed to replace polysilicon as a multi-purpose material in MEMS but it has not been yet explored as a bimorph material. Under this premise, an in-plane bimorph actuator based on doped polycrystalline silicon carbide and silicon was proposed to ...
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  Mentions: Delft University of Technology
19. Polarization-Maintaining Fiber-Based Optical Coherence Tomography And Its Applications (Thesis)
  
  Explore University Digital Conservancy Home Nov 10 2015 Student Theses
  
  Recent advances in Optical Coherence Tomography (OCT) have enabled wide ranges of attractive applications, including characterization of biological tissues, morphological tracking, intravascular imaging, developmental biology and in functional spectroscopic aspects. Neural activity has been studied using optical methods in the past few decades. The use of light to probe neural activity allows outstanding resolution, and the possibility for simultaneous measurement from a range of targeted locations without physical contact with the tissue. Optically detectable signals, such as transient changes with phase and backscattered light intensity, are captured using spectral-domain OCT system. In this dissertation, a fundamental introduction to polarization-maintaining fiber-based ...
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  Mentions: University of Michigan
20. Ophthalmic Application of Optical Coherence Tomography Based Angiography for Choroidal Imaging (Thesis)
  
  Explore digital.lib.washington.edu Oct 6 2015 Student Theses
  
  We demonstrated in vivo choriocapillaris imaging in normal human subjects with a Cirrus HD 5000 spectral domain OCT prototype. With the tracking system installed in the prototype and the montage scanning protocol, wide field OCT angiograms of 9 mm * 11 mm were created. OCT angiography utilizes the intrinsic motion of red blood cells as contrast mechanism therefore requires no exogenous contrast agents as fluorescein angiography and indocyanine green angiography do. Four consecutive OCT scans were acquired at the same location for angiography generating, intensity based, phase based and complex signal based OCTA were all computed and compared. With the ability ...
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  Mentions: University of Washington Zeiss Cirrus HD-OCT
21. Development and Application of Optical Coherence Elastography for Corneal Biomechanics (Thesis)
  
  Explore OhioLINK ETD Center Sep 8 2015 Ophthalmology , Student Theses
  
  The biomechanical properties of the cornea are an important determinant of both the shape and function of the human visual system. Measuring the biomechanical properties on an in vivo basis requires the development of technologies not typically associated with mechanical measurement. Optical Coherence Elastography (OCE) is an optical based measurement capable of measuring micron level displacements in accessible tissues. The application of OCE to corneal measurement was made possible by the use of speckle tracking in the corneal stroma. Application of OCE to human donor corneas was used to measure the biomechanical properties of the human cornea in three separate ...
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  Mentions: Case Western Reserve University
22. Development of Photothermal Optical Coherence Tomography for In Vivo Imaging of Contrast Agents (Thesis)
  
  Explore ETD - Electronic Theses & Dissertations Aug 4 2015 Student Theses
  
  Sensitive and specific noninvasive in vivo imaging of contrast agents and endogenous molecules can supply molecular and functional information in animal models, providing essential insight into mechanisms of disease formation and progression, drug delivery, and treatment response. In cancer in particular, high resolution imaging is essential for capturing spatial heterogeneities in molecular expression and the tumor microenvironment that cause significant barriers to treatment efficacy and drug delivery. Optical coherence tomography (OCT) fills the niche of cellular-level resolution and penetration depths in tissue that exceed those obtained with microscopy, an attractive regime for imaging mouse models of cancer. In this dissertation ...
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  Mentions: Vanderbilt University
23. Design and Fabrication of Optical Polymer Waveguide Devices for Optical Interconnects and Integrated Optical Coherence Tomography (Thesis)
  
  Explore Scholarly Repository Aug 1 2015 Student Theses
  
  Optical interconnects is a promising technique to boost the speed of electronic systems through replacing high speed electrical data buses using optical ones. Optical coherence tomography is an attractive imaging technique that has been widely used in medical imaging applications with capability of high resolution subsurface cross sectional imaging in living tissues. Both the optical interconnects and the optical coherence tomography imaging may benefit from the use of integrated optics technology in particular polymer waveguides that can be designed and fabricated to improve the device capability, system compactness, and performance reliability. In this dissertation, we first present our innovative design ...
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  Mentions: University of Miami
24. Speckle And Motion Based Vascular Image Analysis for Optical Coherence Tomography (Thesis)
  
  Explore TSpace Repository Jul 28 2015 Cardiology , Student Theses
  
  Optical Coherence Tomography (OCT) is an emerging optical imaging modality that is capable of imaging biological tissues with micron resolution and millimeter penetration depth. In clinical diagnostic imaging and pathology, OCT has helped fill a gap in terms of both resolution and imaging depth, in between traditional fluoroescence based microscopes and non-invasive organ level imaging. In this domain, OCT can be used both as an ex vivo pathological examination tool or in vivo imaging modality.OCT has been successful in ophthalmology owing to its excellent in vivo optical sectioning ability and penetration depth. Over the years, OCT has seen substantial ...
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  Mentions: University of Toronto Victor X. D. Yang
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