Optical Tomography and Spectroscopy of Tissue XVI

Medical imaging based on near infrared (NIR) illumination is a powerful and cost-effective approach for characterizing thick tissues non-invasively. Technological developments using principles of Diffuse Optical Spectroscopy (DOS), Diffuse Optical Imaging (DOI), Diffuse Optical Tomography (DOT), and Diffuse Correlation Spectroscopy (DCS) have helped drive significant advances in quantitative, model-based NIR methods. Diffuse optical technologies account for the effects of multiple light scattering in tissue and have been applied to a broad variety of problems in biology and medicine spanning from cancer and wound healing to muscle function and brain imaging.

Many of these methods are designed to provide functional diagnostic information about tissue physiology in real or near-real time. Endogenous hemoglobin absorption and tissue scattering provides a particularly powerful and unique capability of diffuse optical methods in their ability to measure tissue oxygen utilization and blood perfusion. Quantification of other tissue constituents can also effectively contribute to physiological studies as well as diagnostic applications. The temporal analysis of intensity fluctuations in diffuse correlation spectroscopy provides measurements of blood flow in tissue. Exogenous optical contrast agents that introduce absorption, fluorescence, or scattering biomarkers that are predictive of disease and clinical outcome are a topic of major interest and activity. The combination of intrinsic and extrinsic contrast elements into multi-modality DOI platforms provides functional, dynamic images with capabilities that rival, and in some cases exceed, conventional radiologic imaging approaches. Similarly, the combination of diffuse optical methods with established anatomic imaging technologies such as MRI, ultrasound, and x-ray imaging is a powerful strategy that can significantly enhance information content. As a result, diffuse optical methods provide cost-effective solutions for diagnostic imaging and therapeutic guidance as either "stand-alone" or integrated "multi-modality" platforms.

This conference emphasizes all aspects of diffuse optical methods in tissues, including theoretical, modeling, and data analysis approaches, novel hardware and instrumentation, and applications in human subjects and pre-clinical models.

Suggested topics include the following:

Theory, modeling, and data analysis

• Advances in the formulation of forward and inverse problems, methods that account for tissue heterogeneity, and understanding limits of image resolution, contrast, and signal-to-noise ratio;
• Transport theory, diffusion theory, Monte Carlo simulations, numerical methods;
• Fundamental properties of photon density waves (PDW) and methods for control and measurement of PDWs;
• Theory, models, and methods for DCS measurements;
• Deep learning, machine learning, and artificial intelligence for diffuse optics.

Instrumentation and methods

• Novel hardware, probe, and imaging designs including improved signal processing, advances in sources and detectors, novel imaging geometries to enhance speed, signal-to-noise ratio, and information content;
• Tissue phantoms and protocols for performance assessment;
• Multi-modality platforms, image co-registration and data visualization;
• Methods to elucidate the physiological meaning of endogenous optical contrast, including dynamic signals, vascular reactivity, and effects of dynamic perturbations;
• Specialized technologies for small animal model imaging;
• Exogenous absorption, scattering, and fluorescence contrast agents for enhanced cellular and molecular specificity;
• Cost-effectiveness, reducing barriers to access, and miniaturization of instrumentation;
• Design and applications of wearable devices;

Applications

• Non-invasive cerebral spectroscopy and imaging: normal brain function, neuro-degeneration, brain trauma, and neuro-pathologies;
• Non-invasive spectroscopy and imaging of skeletal-muscular systems, including joints, bones, and muscle;
• Non-invasive spectroscopy and imaging of normal breast function, hormonal stimulation, disease risk, breast pathologies, and monitoring of response to cancer therapy;
• Spectroscopy and imaging of tissues for diagnostic evaluations or physiological monitoring;
• Spectroscopy and imaging of tissue for monitoring therapeutic interventions such as response to chemo-, radiation-, preventative, and hormonal therapies;
• Image-guided diagnosis, treatment, therapy, and surgical planning;
• Correlation of optical imaging biomarkers with gold standard methods, clinical endpoints, and validation in multi-center settings;
• Preventive and screening applications;
• Minimally-invasive, intra-operative settings.