Multimodal photoacoustic remote sensing (PARS) microscopy combined with swept-source optical coherence tomography (SS-OCT) for in-vivo, non-contact, functional and structural ophthalmic imaging applications

Ophthalmic imaging has long played an important role in the understanding, diagnosis, and treatment of a wide variety of ocular disorders. Currently, available clinical ophthalmic imaging instruments are primarily optical-based, including slit-lamp microscopy, fundus photography, confocal microscopy, scanning laser ophthalmoscopy, and optical coherence tomography (OCT). The development of these imaging instruments has greatly extended our ability to evaluate the ocular environment. Studies have shown that at least 40% of blinding disorders in the United States are either preventable or treatable with timely diagnosis and intervention. OCT is a state-of-the-art imaging technique extensively used in preclinical and clinical applications for imaging both anterior and posterior parts of the eye. OCT has become a standard of care for the assessment and treatment of most ocular conditions. The technology enables non-contact, high-speed, cross-sectional imaging over a large field of view with submicron resolutions. In eye imaging applications, functional extensions of OCT such as spectroscopic OCT and Doppler OCT have been applied to provide a better understanding of tissue activity. Spectroscopic OCT is usually achieved through OCT systems in the visible spectral range, and it enables the amount of light absorption inside the ocular environment to be measured. This indirect optical absorption measurement is used to estimate the amount of ocular oxygen saturation (SO2) which is a well-known biomarker in prevalent eye diseases including diabetic retinopathy, glaucoma, and retinal vein occlusions. Despite all the advancements in functional spectroscopic OCT methods, they still rely primarily on measuring the backscattered photons to quantify the absorption of chromophores inside the tissue. Therefore, they are sensitive to local geometrical parameters, such as retinal thickness, vessel diameters, and retinal pigmentation, and may result in biased estimations. Of the various optical imaging modalities, photoacoustic imaging (PAI) offers unique imaging contrast of optical absorption because PAI can image any target that absorbs light energy. This unique imaging ability makes PAI a favorable candidate for various functional and molecular imaging applications as well as for measuring chromophore concentration. Over the past decade, photoacoustic ophthalmoscopy has been applied for visualizing hemoglobin and melanin content in ocular tissue, quantifying ocular SO2, and measuring the metabolic rate of oxygen consumption (MRO2). Despite all these advantages offered by PAI devices, a major limitation arises from their need to be in contact with the ocular tissues. This physical contact may increase the risk of infection and cause patient discomfort. Furthermore, this contact-based imaging approach applies pressure to the eye and introduces barriers to oxygen diffusion. Thus, it has a crucial influence on the physiological and pathophysiological balance of ocular vasculature function, and it is not capable of studying dynamic processes under normal conditions. To overcome these limitations and to benefit from the numerous advantages offered by photoacoustic ophthalmoscopy, non-contact detection of photoacoustic signals has been a long-lasting goal in the field of ocular imaging. In 2017 Haji Reza et al. developed photoacoustic remote sensing (PARS) for non-contact, non-interferometric detection of photoacoustic signals. PARS is the non-contact, all-optical version of optical-resolution photoacoustic microscopy (OR-PAM), where the acoustically coupled ultrasound transducer is replaced with a co-focused probe beam. This all-optical detection scheme allows the system to measure the photoacoustic pressure waves at the subsurface origin where the pressure is at a maximum. In a very short time, PARS technology has proven its potential for various biomedical applications, including label-free histological imaging, SO2 mapping, and angiogenesis imaging. PARS is an ideal companion for OCT in ophthalmic applications, where the depth-resolved, detailed scattering information of OCT is well complemented by rich absorption information of PARS. This combined multimodal imaging technology has the potential to provide chromophore selective absorption contrast in concert with depth-resolved scattering contrast in the ocular environment. The main goals of this PhD project are to: • Develop a photoacoustic remote sensing microscopy system for in-vivo, non-contact ophthalmic imaging. This is the first time a non-contact photoacoustic imaging has been used for in-vivo imaging of the eye. • Develop a robust and temporally stable multiwavelength light source for functional photoacoustic imaging applications. • Develop a multimodal PARS-OCT imaging system that can image in-vivo and record, simultaneously, functional, and structural information in the anterior segment of a rodent eye. This is the first time a multiwavelength non-contact photoacoustic system is used for in-vivo measurement of oxygen saturation in the ocular environment. • Develop and modify the multimodal PARS-OCT imaging system for non-contact, in-vivo, functional, and structural imaging of the posterior part of the rodent eye

Enhanced Liposuction

Liposuction began as a simple, minimally invasive method of reducing the amount of localized fat in a region. Today it is a sophisticated and complex process, with many variations in purpose and technique. In this book, a global slate of expert surgeons offers a detailed description of various minimally invasive and non-invasive options for contouring the face, neck, and body. Chapters detail the evolution and utilization of various energy-based devices and combination treatments. They also describe procedure limitations and treatment of complications. Finally, they discuss indications for various approaches with case study descriptions so readers might be assisted with treating patients in their everyday practice

Optical Diagnostics in Human Diseases

Optical technologies provide unique opportunities for the diagnosis of various pathological disorders. The range of biophotonics applications in clinical practice is considerably wide given that the optical properties of biological tissues are subject to significant changes during disease progression. Due to the small size of studied objects (from μm to mm) and despite some minimum restrictions (low-intensity light is used), these technologies have great diagnostic potential both as an additional tool and in cases of separate use, for example, to assess conditions affecting microcirculatory bed and tissue viability. This Special Issue presents topical articles by researchers engaged in the development of new methods and devices for optical non-invasive diagnostics in various fields of medicine. Several studies in this Special Issue demonstrate new information relevant to surgical procedures, especially in oncology and gynecology. Two articles are dedicated to the topical problem of breast cancer early detection, including during surgery. One of the articles is devoted to urology, namely to the problem of chronic or recurrent episodic urethral pain. Several works describe the studies in otolaryngology and dentistry. One of the studies is devoted to diagnosing liver diseases. A number of articles contribute to the studying of the alterations caused by diabetes mellitus and cardiovascular diseases. The results of all the presented articles reflect novel innovative research and emerging ideas in optical non-invasive diagnostics aimed at their wider translation into clinical practice

Ames Research Center publications: A continuing bibliography, 1980

This bibliography lists formal NASA publications, journal articles, books, chapters of books, patents, contractor reports, and computer programs that were issued by Ames Research Center and indexed by Scientific and Technical Aerospace Reports, Limited Scientific and Technical Aerospace Reports, International Aerospace Abstracts, and Computer Program Abstracts in 1980. Citations are arranged by directorate, type of publication, and NASA accession numbers. Subject, personal author, corporate source, contract number, and report/accession number indexes are provided

Texas Register

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code

University catalog, 2016-2017

The catalog is a comprehensive reference for your academic studies. It includes a list of all degree programs offered at MU, including bachelors, masters, specialists, doctorates, minors, certificates, and emphasis areas. It details the university wide requirements, the curricular requirements for each program, and in some cases provides a sample plan of study. The catalog includes a complete listing and description of approved courses. It also provides information on academic policies, contact information for supporting offices, and a complete listing of faculty members. -- Page 3

Advance in Composite Gels

In the last few decades, various composite gels have been developed. In recent years, further advances have been made in the development of novel composite gels with potential applications in various fields. This reprint offers the latest findings of composite gels by experts throughout the world