The present study describes the design and validation of a simple apparatus to apply simultaneous mechanical and fluidic stress to three-dimensional (3D) cell-seeded collagen hydrogels. Constructs were formed in wells in a silicone substrate that could be stretched cyclically, and were also fitted with inlet ports to apply fluid flow. Acid etching was used to retain adhesion of the gels to the ...

BACKGROUND The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human m...

Analysing heart motion provides crucial insights on the condition of the cardiac function. Tagged-MRI and 2D-strain ultrasound enable quantitative assessment of the myocardium strain. But estimating 3D myocardium strain from cine-MRI remains attractive: cine-MRI is widely available and it yields detailed 3D+t anatomical images. This paper presents an image-based method to estimate myocardium st...

During traumatic spinal cord injury (SCI), the spinal cord is subject to external displacements that result in damage of neural tissues. These displacements produce complex internal deformations, or strains, of the spinal cord parenchyma. The aim of this study is to determine a relationship between these internal strains during SCI and primary damage to spinal cord gray matter (GM) in an in viv...

MRI provides a valuable tool for noninvasive evaluation of myocardial wall motion. Recently, multi-phase 2D DENSE MRI was developed to quantify cardiac strain in mice at high spatial and temporal resolution [1, 2]. DENSE methods for 3D displacement encoding have also been investigated [3]. Typically, these methods entail multiple acquisitions that are time consuming. In this project, we aimed t...

A novel approach to determine the structure of nanoscale crystals in three dimensions is proposed by the use of coherent x-ray Fourier transform holography in Bragg geometry. The full internal description is directly obtained by a single Fourier transform of the 3D intensity hologram. Together with the morphology, Bragg geometry gives access to the 3D displacement field within the crystal. This...

It is remarkable that the pathological state of human soft tissues highly correlates with static and low-frequency mechanical properties, particularly shear elasticity (e.g., Sumi, 2005d). Accordingly, we have been developing ultrasonic (US)-strain-measurement-based onedimensional (1D) (Sumi et al., 1993, 1995a, 2010f; Sumi, 1999b, 2005d, 2008a, 2010d; Sumi & Matsuzawa, 2007b), 2D (Sumi et al.,...

This paper presents a physics-based approach to obtain 2D or 3D dynamic pedobarography transitional objects from two given images (2D or 3D). With the used methodology, we match nodes of the input objects by using modal matching, improved with optimization techniques, and solve the Lagrangian dynamic equilibrium equation to obtain the intermediate shapes. The strain energy involved can also be ...

We describe an automated, model-based method to segment the left and right ventricles in 4D tagged MR. We fit 3D epicardial and endocardial surface models to ventricle features we extract from the image data. Excellent segmentation is achieved using novel methods that (1) initialize the models and (2) that compute 3D model forces from 2D tagged MR images. The 3D forces guide the models to patie...