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Relating optical coherence tomography to visual fields in glaucoma: structure–function mapping, limitations and future applicationsDenniss, Jonathan, Turpin, A., McKendrick, A.M. 29 November 2018 (has links)
Yes / Combining information from optical coherence tomography (OCT) imaging and visual field testing is useful in the clinical assessment and monitoring of patients with glaucoma. Measurements of retinal nerve fibre layer thickness or neuroretinal rim width taken around the optic nerve head may be related to the visual field using a structure–function map. In this review, the structure–function mapping methods in clinical use are discussed. Typical clinical maps provide a population average, ‘one size fits all’ representation, but in recent years methods for customising structure–function maps to individual eyes have been developed and these are reviewed here. In the macula, visual field stimuli stimulate photoreceptors for which associated retinal ganglion cells are peripherally displaced. Recently developed methods that relate OCT measurements to visual field test locations in the macula are therefore also reviewed. The use of structure–function maps to relate OCT measurements to localised visual field sensitivity in new applications is also explored. These new applications include the selection of visual field test locations and stimulus intensities based on OCT data, and the formal post‐test combination of results across modalities. Such applications promise to exploit the structure–function relationship in glaucoma to improve disease diagnosis and monitoring of progression. Limitations in the validation and use of current structure–function mapping techniques are discussed. / >Heidelberg Engineering >Australian Research Council. Grant Number: LP130100055 >College of Optometrists. Grant Number: College of Optometrists Research Fellowship
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Flytten utan sammanhang : En kvalitativ studie om professionellas syn på ungdomar som omplaceras mellan SiS och HVB.Moss, Erik, Kindkvist, Jimmy January 2016 (has links)
Uppsatsen handlar om tre verksamhetschefers och en behandlingsassistents uppfattningar om hur ungdomar som vistas på Hem för vård och boende (HVB)- eller Statens Institutionsstyrelse –hem (SiS, som kan använda låsbara avdelningar), påverkas av de omplaceringar som sker när ungdomen flyttar från SiS till HVB. I den här studien fokuserar vi på en specifik del i behandlingen, som kan påverka ungdomar som är vårdplacerade – omplaceringar mellan vårdboenden. Vi undersöker bland annat hur dessa omplaceringar går till/skulle kunna gå till, samt vilka anledningar som kan tänkas vara bakgrunden till att en ungdom omplaceras. Som underlag för vår studie har vi utöver litteratur och forskning inom området, genomfört fyra intervjuer med personal från HVB och SiS boenden. Vi använder anknytningsteorin och Sense of coherence modellen som teoretisk referensram. Resultatet visar att det finns brister gällande omplaceringar. Samtliga informanter önskade mer tid till förberedelserna i arbetet med ungdomen som ska flytta in. Ett önskemål vore att det från beslut till inflyttning skulle ta 3-6 månader, då det ger möjlighet för personalen på det nya boendet att besöka ungdomen och börja knyta band redan innan flytten ska genomföras. Slutsatsen blir att omplaceringen spelar roll för ungdomens behandling och vistelse på boendet. Samtidigt är det oroväckande att det saknas tydliga riktlinjer för hur dessa omplaceringar ska ske. Om mer resurser och tydligare riktlinjer kring omplaceringar gavs, kan det minska det antal omplaceringar där ungdomen tvingas flytta tillbaka till SiS. Idag får ungefär var fjärde ungdom flytta tillbaka igen. / This paper investigates the perspective of managers' and processing staffs concerning young people living on a Home for care or living(HVB)- or Institutional board of the states- home (SiS - they can use lockable departments), and how they think youths are affected by the transfer between SiS and HVB. This study focus on factors that can affect young people's health - replacing youths between different nursing homes. The paper investigates how these replacements are performed/could be performed, as well as the underlying factors that might explain why a youth is being relocated. As a basis for our study, in addition to the literature and research in the field, we have conducted four interviews with personnel from HVB- and SiS- accommodations. We use the attachment theory and the Sense of coherence theory as a theoretical frame. The results show that there are shortcomings in the process of redeployment. All informants wanted more time to prepare the work of a youth who is about to move. A proposal from the informants, was that the process from decision to the actual moving should take between 3-6 months. This would give the staff in the new accommodation a chance to visit the youth and begin to build ties, before the move is implemented. The conclusion is that the transfer has an important role in the treatment and the stay of the youth. At the same time, it is of great concern that there are no clear guidelines for how these replacements should be performed. If there would be more resources and clearer guidelines for how redeployments should be handled, it might perhaps reduce the number of shifts where young people are moving back to SiS. Today approximately one of four youth needs to move back.
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The relationship between emotional intelligence, locus of control sense of coherence in a market research organisationFeldman, Janine 02 1900 (has links)
The primary objective was to determine whether there is a relationship between emotional
intelligence, locus of control and sense of coherence in a market research organisation. A
secondary objective was to determine whether individuals from various biographical groups
differed significantly in terms of emotional intelligence, locus of control and sense of coherence. A
sample of 179 participants completed the Bar-On EQ-i, Locus of Control Inventory and Sense of
Coherence Scale.
There was a statistically significant relationship between emotional intelligence, locus of control
and sense of coherence. No significant gender differences were found. Furthermore, the findings
showed differences between occupational levels in terms of both internal locus of control and
sense of coherence, but not for emotional intelligence. No significant differences were evident
between education, work experience or age in terms of the three constructs.
An emotional intelligence intervention programme was recommended, as well as the use of an
emotional intelligence assessment instrument. Recommendations for future research included
broadening the relevance of the results. / Industrial and Organisational Psychology / M.A. (Industrial and Organisational Psychology)
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KASAM och stress - här och nu : Perspektiv i samtida svensk forskning som använder SOC-skalan som verktyg: en litteraturöversikt / Sense of coherence and stress – here and now : Perspectives of contemporary Swedish research using the SOC scale as an instrument: a literature reviewCarlqvist Warnborg, Ylva January 2016 (has links)
Abstrakt Bakgrund: Antonovskys sense of coherence (SOC)/känsla av sammanhang (KASAM) är ett globalt använt begrepp. Mätverktyget SOC-skalan som förekommer i minst 15 olika versioner används inom många olika vetenskapliga studier. Syftet med denna litteraturöversikt är att beskriva vilka perspektiv och huvudsakliga resultat som lyfts fram i samtida svensk vetenskaplig forskning kring stress som använder SOC-begreppet och SOC-skalan. Metod: Text- och innehållsanalys av forskningsfokus och perspektiv i de senaste fem årens vetenskapliga studier kring stress och sense of coherence i Sverige. Resultat: SOC-skalan används i studier med olika design inom många olika forskningsområden. Dominerande perspektiv i samtida svensk forskning med SOC-skalan som huvudsakligt eller kompletterande verktyg är det holistiska perspektivet, individperspektivet, genusperspektivet samt föräldraperspektivet. Diskussion: SOC-skalans vetenskapliga användning speglar dagens svenska samhälls- och diskussionsklimat. SOC-skalans validitet och reliabilitet förblir föremål för diskussion, då olika versioner av SOC-skalan ger olika resultat och olika möjligheter till analys. / Abstract Background: Antonovsky’s sense of coherence (SOC) is a globally used concept. The SOC scale tool exists in at least 15 different versions and is used in many different scientific studies. The aim of this literature review is to describe which perspectives and main results are highlighted in contemporary Swedish research concerning stress that uses the SOC concept and the SOC scale. Method: Text and content analysis concerning research focus and perspectives in scientific studies concerning stress and sense of coherence in Sweden in the last five years. Results: The SOC scale is used in studies of different designs within many different fields of research. Dominating perspectives in contemporary Swedish research using the SOC scale as a main or complementary tool are the holistic perspective, the individual perspective, the gender perspective and the parental perspective. Discussion: The scientific use of the SOC scale reflects the social discussion climate in Sweden of today. The validity and reliability of the SOC scale remain subjects of discussion, as different versions of the SOC scale give different results and different analyzing possibilities.
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Dynamic Linkage Between Local Cross-frequency Coupling and Communication Through Coherence in an in Vitro Model of Human Neocortical Oscillatory ActivityMcGinn, Ryan J. 05 December 2013 (has links)
The dynamical underpinnings of complex computation and information transmission within the brain, while of great interest to the neuroscience community at large, remain poorly understood. One of the striking manifestations of neuronal population activity is that of rhythmic oscillations in the local field potential. It is thought that distinct patterns of these oscillations such as cross-frequency coupling within a given spatial location and coherence between disparate brain regions may represent neuronal computation and communication, respectively. Here we show such dynamics within a human temporal neocortical in vitro model. In specific, we show theta-gamma cross frequency coupling in deep and superficial layers, phase coherence between layers at theta frequencies, and a measure of communication (phase dependent power correlations) between layers at theta frequency. Additionally, we show a novel correlation between communication across layers and cross frequency coupling within layers, demonstrating a dynamic link between local computation and intralaminar communication.
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Low-coherence interferometer for contact lens surface metrologyHeideman, Kyle C., Greivenkamp, John E. 29 March 2016 (has links)
Contact lens performance depends on a number of lens properties. Many metrology systems have been developed to measure different aspects of a contact lens, but none test the surface figure in reflection to subwavelength accuracy. Interferometric surface metrology of immersed contact lenses is complicated by the close proximity of the surfaces, low surface reflectivity, and instability of the lens. An interferometer to address these issues was developed and is described here. The accuracy of the system is verified by comparison of glass reference sample measurements against a calibrated commercial interferometer. The described interferometer can accurately reconstruct large surface departures from spherical with reverse raytracing. The system is shown to have residual errors better than 0.05% of the measured surface departure for high slope regions. Measurements made near null are accurate to lambda/20. Spherical, toric, and bifocal soft contact lenses have been measured by this system and show characteristics of contact lenses not seen in transmission testing. The measurements were used to simulate a transmission map that matches an actual transmission test of the contact lens to lambda/18. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)
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Evaluation of retinal nerve fiber layer measurement with spectral-domain optical coherence tomography in glaucoma. / CUHK electronic theses & dissertations collectionJanuary 2012 (has links)
青光眼作為一種慢性進展性視神經病變,已經成為世界眼科病變中導致不可逆盲的首要原因。青光眼的早期診斷和治療對於降低疾病進展的風險至關重要。光學相干斷層掃描(OCT)可以提供在體視網膜橫斷面的視圖,從而實現了對視網膜神經纖維層(RNFL)改變的客觀測量,這些改變已經被證明了與青光眼引起的視神經損害相關,並已成為診斷青光眼的重要參考依據。 / 頻域OCT是最新一代的光學相干斷層掃描,它具有比時域OCT更快的掃描速度和更高的圖像解析度,因此,頻域OCT可以提供更可靠的RNFL厚度測量和RNFL缺損評估。本文的研究目的在於評估頻域OCT對RNFL厚度的重測再現性,以及探討影響RNFL厚度測量的因素,這些因素包括(1)影像平均法的應用,(2)RNFL分層錯誤,和(3)視網膜血管的影響。此外,由於RNFL攝影是一個評估青光眼RNFL缺損的臨床參考標準,我們還將其對RNFL缺損的測量與頻域OCT的RNFL厚度偏差圖所作出的測量進行了比較。 / 首先,為了評估頻域OCT對RNFL厚度測量的重測再現性,15名正常人和15名青光眼患者連續四周每週均接受一次OCT掃描。正常組和青光眼組的RNFL厚度再現性係數分別為4.77-12.65微米和4.53-16.66微米,由於組內相關性係數均大於0.773,說明頻域OCT所作出的RNFL厚度測量是具備可重複性的。 / 其次,通過分析54隻眼(25名正常志願者和29名青光眼患者)的RNFL厚度測量值,本文對圖像平均法的應用是否會影響RNFL厚度的測量這一問題進行了探討。分析中,每一隻眼均接受了3次OCT掃描,3次掃描的圖像分別使用2、8、和16張連續的圖像進行影像平均。結果顯示,除了青光眼組的鼻下象限RNFL厚度測量值之外(P=0.036),不同的圖像幀數並不會對兩組的總體和其它各象限的RNFL厚度測量值產生顯著的影響(P≥0.055)。雖然圖像平均法的應用對RNFL厚度測量的影響並不顯著,但是視網膜血管和RNFL分層錯誤對青光眼,尤其是對RNFL非常薄的晚期青光眼患者的RNFL厚度測量有影響。結論來自對60個正常人,66個輕至中度青光眼(MD≥-6 dB)患者和54個嚴重青光眼(MD<-6 dB)患者的共180張OCT圖像的分析。視網膜血管相對於平均RNFL厚度的比例均值在正常組,輕至中度青光眼組,和嚴重青光眼組分別為11.2±2.3,12.6±2.5,和16.6±3.9。在人為調整了RNFL界限以糾正RNFL分層錯誤的前後,總體RNFL厚度的差異範圍在正常組為-3.0-2.5微米,輕至中度青光眼組為-2.5-5.0微米,嚴重青光眼組為-11.0-9.5微米組。 / 最後,通過對41名青光眼患者的51隻眼的RNFL缺損面積,位置,和覆蓋角度進行測量,本文將頻域OCT作出的測量結果和共焦鐳射掃描檢眼鏡(CSLO)RNFL反射影像圖的測量結果進行了比較,結果顯示:OCT不但可以檢測到所有出現在CSLO的RNFL反射影像圖上的RNFL缺損,更重要的是,OCT還可以檢測出額外的並未在RNFL反射影像圖上出現的RNFL缺損。 / 總之,頻域OCT是一種可提供高再現性RNFL厚度測量的影像方法。對青光眼,尤其是晚期青光眼的RNFL厚度測量值的詮釋,應當考慮到視網膜血管和RNFL分層錯誤的影響。OCT具備對RNFL缺損進行多維度量化(包括厚度,面積,位置,和覆蓋角度)的能力,在青光眼RNFL改變的檢測和監測方面,相對于傳統的RNFL攝影,OCT無疑是更有效的選擇。 / Glaucoma, a chronic progressive optic neuropathy, is the leading cause of irreversible blindness in the world. An early diagnosis and treatment of glaucoma is vital to reduce the risk of disease progression. Providing a cross-sectional view of the retina in vivo, optical coherence tomography (OCT) can objectively measure the changes of retinal nerve fiber layer (RNFL), which has been shown to be of relevance and importance in detecting glaucomatous damage of the optic nerve. / The latest generation of OCT, the spectral-domain OCT, has a faster scan speed and a higher image resolution compared to the time-domain OCT. It is expected that the spectral-domain OCT would allow a more reliable measurement of the RNFL thickness and assessment of RNFL defects. The objectives of this research project were to examine the test-retest reproducibility of spectral-domain OCT RNFL measurement and investigate factors including (1) image averaging, (2) segmentation failure, and (3) contribution of retinal blood vessels that might affect the measurement of RNFL thickness. As RNFL photography is a reference standard to evaluate RNFL defects in glaucoma, we also evaluated whether RNFL defects measured in the spectral-domain OCT RNFL thickness map would be comparable to those detected in RNFL photographs. / To evaluate the test-retest reproducibility of RNFL measurements obtained by the spectral-domain OCT, 15 normal individuals and 15 glaucoma patients were followed and imaged weekly for 4 consecutively weeks. The reproducibility coefficients of RNFL thicknesses ranged between 4.53 and 16.66 μm for the normal group, and 4.77 and 12.65 μm for the glaucoma group. The intraclass correlation coefficients were all above 0.773, indicating RNFL measurement with spectral-domain OCT was reproducible. / We then investigated if multiple-image averaging would influence the measurement of RNFL thickness. A total of 54 eyes from 25 normal volunteers and 29 glaucoma patients with RNFL images captured and averaged with 2, 8, and 16 consecutive image frames were analyzed. For both groups, there were no significant differences in global or sectoral RNFL thicknesses among the image series averaged with different number of image frames (all with P≥0.055) except for the inferonasal sector in the glaucoma group (P=0.036). Although the impact of image averaging on RNFL measurement was insignificant, the presence of retinal blood vessels and segmentation errors were influential on the measurement, particularly in advanced glaucoma patients when the RNFL was thin. Analyzing a total of 180 eyes from 60 normal individuals, 66 mild to moderate (MD≥-6 dB) and 54 advanced (MD<-6 dB) glaucoma patients, the mean proportion of retinal blood vessels relative to the average RNFL thickness was 11.2±2.3%, 12.6±2.5% and 16.6±3.9%, respectively. After correcting the segmentation errors by manually refining the RNFL boundaries, the differences in average RNFL thickness ranged from -3.0 to 2.5 m in the normal, -2.5 to 5.0 m in the mild to moderate glaucoma and -11.0 to 9.5 m in the advanced glaucoma groups. / Finally, we compared the area, the angular location, and the angular width of RNFL defects from 51 eyes of 41 glaucoma patients measured with the spectral-domain OCT and RNFL reflectance images obtained by a confocal scanning laser ophthalmoscope (CSLO). OCT was able to detect areas of RNFL abnormalities in all eyes with RNFL defects which were evident in the CSLO RNFL reflectance images. More important, OCT could identify additional RNFL thinning not apparent in RNFL reflectance images. / In summary, spectral-domain OCT could offer an effective approach in measuring RNFL with high reproducibility. Interpretation of RNFL measurement should take the contribution of the retinal blood vessels and segmentation errors into consideration, particularly in advanced glaucoma when the RNFL is thin. With the ability to quantify multiple dimensions of RNFL defects (thickness, area, angular location, and angular width), OCT could provide a useful alternative to detect and monitor RNFL changes in glaucoma. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Ye, Cong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 117-130). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / ABSTRACT --- p.i / 摘要 (ABSTRACT IN CHINESE) --- p.v / DEDICATION --- p.viii / ACKNOWLEDGEMENT --- p.ix / TABLE OF CONTENTS --- p.x / PUBLICATIONS --- p.xiv / ABBREVIATIONS --- p.xvi / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Glaucoma --- p.2 / Definition of Glaucoma --- p.2 / Epidemiology of Glaucoma --- p.3 / Pathogenesis of Glaucoma --- p.4 / Diagnosis of Glaucoma --- p.7 / Chapter 1.2 --- Retinal Nerve Fiber Layer --- p.13 / Anatomy of Retinal Nerve Fiber Layer --- p.13 / Visualization of Retinal Nerve Fiber Layer --- p.14 / Retinal Nerve Fiber Layer Defect in Glaucoma --- p.16 / Significance of Detecting Retinal Nerve Fiber Layer Defect in Glaucoma --- p.18 / Chapter 1.3 --- Optical Coherence Tomography --- p.20 / Principle of Optical Coherence Tomography --- p.20 / Retinal Nerve Fiber Layer Imaging with OCT --- p.21 / Optic Nerve Head Imaging with OCT --- p.27 / Advantages and Disadvantages of Optical Coherence Tomography --- p.29 / Chapter 1.4 --- Research Objectives --- p.30 / Chapter CHAPTER 2: --- GENERAL MATERIALS AND METHODS --- p.32 / Chapter 2.1 --- Subject Enrollments --- p.33 / Chapter 2.2 --- Clinical Ophthalmic Examination --- p.34 / Chapter 2.3 --- Visual Field Examination --- p.35 / Definition of Normal and Glaucoma Groups --- p.35 / Chapter 2.4 --- Optical Coherence Tomography Imaging --- p.37 / Cirrus HD-OCT Imaging --- p.37 / Spectralis OCT Imaging --- p.37 / Chapter 2.5 --- Statistical Analysis --- p.39 / Chapter CHAPTER 3: --- RETINAL NERVE FIBER LAYER IMAGING WITH SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY --- p.40 / Chapter 3.1 --- Reproducibility and Agreement of Retinal Nerve Fiber Layer Measurement --- p.41 / Introduction and Study Objectives --- p.41 / Methods --- p.42 / Results --- p.45 / Discussion --- p.47 / Tables and Figures --- p.51 / Chapter 3.2 --- Effect of Multiple B-scans Averaging on Retinal Nerve Fiber Layer Measurement --- p.58 / Introduction and Study Objectives --- p.58 / Methods --- p.59 / Results --- p.61 / Discussion --- p.62 / Tables and Figures --- p.67 / Chapter 3.3 --- Impact of Blood Vessels and Segmentation Failure on Retinal Nerve Fiber Layer Measurement --- p.73 / Introduction and Study Objectives --- p.73 / Methods --- p.75 / Results --- p.78 / Discussion --- p.80 / Tables and Figures --- p.84 / Chapter 3.4 --- Agreement of Localized Retinal Nerve Fiber Layer Defect Assessment with Confocal Scanning Laser Ophthalmoscopy --- p.95 / Introduction and Study Objectives --- p.95 / Methods --- p.97 / Results --- p.101 / Discussion --- p.103 / Tables and Figures --- p.108 / Chapter CHAPTER 4: --- GENERAL CONCLUSIONS --- p.115 / REFERENCES --- p.117
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Development of a Fourier Domain Low Coherence Interferometry Optical System for Applications in Early Cancer DetectionGraf, Robert Nicholas January 2009 (has links)
<p>Cancer is a disease that affects millions of people each year. While methods for the prevention and treatment of the disease continue to advance, the early detection of precancerous development remains a key factor in reducing mortality and morbidity among patients. The current gold standard for cancer detection is the systematic biopsy. While this method has been used for decades, it is not without limitations. Fortunately, optical detection of cancer techniques are particularly well suited to overcome these limitations. This dissertation chronicles the development of one such technique called Fourier domain low coherence interferometry (fLCI). </p><p>The presented work first describes a detailed analysis of temporal and spatial coherence. The study shows that temporal coherence information in time frequency distributions contains valuable structural information about experimental samples. Additionally, the study of spatial coherence demonstrates the necessity of spatial resolution in white light interferometry systems. The coherence analysis also leads to the development of a new data processing technique that generates depth resolved spectroscopic information with simultaneously high depth and spectral resolution. </p><p>The development of two new fLCI optical systems is also presented. These systems are used to complete a series of controlled experiments validating the theoretical basis and functionality of the fLCI system and processing methods. First, the imaging capabilities of the fLCI system are validated through scattering standard experiments and animal tissue imaging. Next, the new processing method is validated by a series of absorption phantom experiments. Additionally, the nuclear sizing capabilities of the fLCI technique are validated by a study measuring the nuclear morphology of in vitro cell monolayers.</p><p>The validation experiments set the stage for two animal studies: an initial, pilot study and a complete animal trial. The results of these animal studies show that fLCI can distinguish between normal and dyplastic epithelial tissue with high sensitivity and specificity. The results of the work presented in this dissertation show that fLCI has great potential to develop into an effective method for early cancer detection.</p> / Dissertation
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Statistical Estimation of Two-Body Hydrodynamic Properties Using System IdentificationXie, Chen 14 January 2010 (has links)
A basic understanding of the hydrodynamic response behavior of the two-body system is
important for a wide variety of offshore operations. This is a complex problem and
model tests can provide data that in turn can be used to retrieve key information
concerning the response characteristics of such systems. The current study demonstrates
that the analysis of these data using a combination of statistical tools and system
identification techniques can efficiently recover the main hydrodynamic parameters
useful in design.
The computation of the statistical parameters, spectral densities and coherence functions
provides an overview of the general response behavior of the system. The statistical
analysis also guides the selection of the nonlinear terms that will be used in the reverse
multi-input / single-output (R-MI/SO) system identification method in this study. With
appropriate linear and nonlinear terms included in the equation of motion, the R-MISO
technique is able to estimate the main hydrodynamic parameters that characterize the
offshore system. In the past, the R-MISO method was primarily applied to single body
systems, while in the current study a ship moored to a fixed barge was investigated. The formulation included frequency-dependant hydrodynamic parameters which were
evaluated from the experimental measurements. Several issues specific to this extension
were addressed including the computation load, the interpretation of the results and the
validation of the model. Only the most important cross-coupling terms were chosen to
be kept based on the estimation of their energy. It is shown that both the heading and the
loading condition can influence system motion behavior and that the impact of the wave
in the gap between the two vessels is important. The coherence was computed to verify
goodness-of-fit of the model, the results were overall satisfying.
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Analog Signal Processing for Optical Coherence Imaging SystemsXu, Wei January 2006 (has links)
Optical coherence tomography (OCT) and optical coherence microscopy (OCM) are non-invasive optical coherence imaging techniques, which enable micron-scale resolution, depth resolved imaging capability. Both OCT and OCM are based on Michelson interferometer theory. They are widely used in ophthalmology, gastroenterology and dermatology, because of their high resolution, safety and low cost. OCT creates cross sectional images whereas OCM obtains en face images. In this dissertation, the design and development of three increasingly complicated analog signal processing (ASP) solutions for optical coherence imaging are presented.The first ASP solution was implemented for a time domain OCT system with a Rapid Scanning Optical Delay line (RSOD)-based optical signal modulation and logarithmic amplifier (Log amp) based demodulation. This OCT system can acquire up to 1600 A-scans per second. The measured dynamic range is 106dB at 200A-scan per second. This OCT signal processing electronics includes an off-the-shelf filter box with a Log amp circuit implemented on a PCB board.The second ASP solution was developed for an OCM system with synchronized modulation and demodulation and compensation for interferometer phase drift. This OCM acquired micron-scale resolution, high dynamic range images at acquisition speeds up to 45,000 pixels/second. This OCM ASP solution is fully custom designed on a perforated circuit board.The third ASP solution was implemented on a single 2.2 mm x 2.2 mm complementary metal oxide semiconductor (CMOS) chip. This design is expandable to a multiple channel OCT system. A single on-chip CMOS photodetector and ASP channel was used for coherent demodulation in a time domain OCT system. Cross-sectional images were acquired with a dynamic range of 76dB (limited by photodetector responsivity). When incorporated with a bump-bonded InGaAs photodiode with higher responsivity, the expected dynamic range is close to 100dB.
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