Reconstructing Haemodynamics Quantities of Interest from Doppler Ultrasound Imaging

The present contribution deals with the estimation of haemodynamics Quantities of Interest by exploiting Ultrasound Doppler measurements. A fast method is proposed, based on the PBDW method. Several methodological contributions are described: a sub-manifold partitioning is introduced to improve the reduced-order approximation, two different ways to estimate the pressure drop are compared, and an error estimation is derived. A test-case on a realistic common carotid geometry is presented, showing that the proposed approach is promising in view of realistic applications.Comment: arXiv admin note: text overlap with arXiv:1904.1336

Physical Principles and Image Creation

While in order to read an ultrasonic image correctly it is necessary to understand how ultrasounds interact with biological tissues and how the ultrasound system constructs the image, this is even more true when studying the thorax due to pulmonary air and the bones of the ribcage that alter the propagation of ultrasounds. For these reasons, this initial chapter, oriented toward practical applications, simply discusses the physical principles that preside over the creation of an ultrasonic image. In particular, it explores how the phenomena of reflection, refraction, scattering, and diffuse reflection affect the creation of thoracic ultrasound images, thus including important notions for resolving interpretive problems and for optimizing equipment settings. The role of these phenomena in generating essential semeiological signs in thoracic ultrasounds, and numerous artefacts will be examined and explored in-depth in the following chapters. Finally, in a simple but exhaustive way, the fundamental aspects of the study of blood flow, both with Doppler applications and through the use of second-generation contrasting mediums, will be addressed

Elastography: modality-specific approaches, clinical applications, and research horizons

Manual palpation has been used for centuries to provide a relative indication of tissue health and disease. Engineers have sought to make these assessments increasingly quantitative and accessible within daily clinical practice. Since many of the developed techniques involve image-based quantification of tissue deformation in response to an applied force (i.e., "elastography"), such approaches fall squarely within the domain of the radiologist. While commercial elastography analysis software is becoming increasingly available for clinical use, the internal workings of these packages often remain a "black box," with limited guidance on how to usefully apply the methods toward a meaningful diagnosis. The purpose of the present review article is to introduce some important approaches to elastography that have been developed for the most widely used clinical imaging modalities (e.g., ultrasound, MRI), to provide a basic sense of the underlying physical principles, and to discuss both current and potential (musculoskeletal) applications. The article also seeks to provide a perspective on emerging approaches that are rapidly developing in the research laboratory (e.g., optical coherence tomography, fibered confocal microscopy), and which may eventually gain a clinical foothold