Volumetric ultrasound imaging has not gained wide recognition, despite the availability of real-time 3D ultrasound
scanners and the anticipated potential of 3D ultrasound imaging in diagnostic and interventional radiology. Their use,
however, has been hindered by the lack of real-time visualization methods that are capable of producing high quality 3D
rendering of the target/surface of interest. Volume rendering is a known visualization method, which can display clear
surfaces out of the acquired volumetric data, and has an increasing number of applications utilizing CT and MRI data.
The key element of any volume rendering pipeline is the ability to classify the target/surface of interest by setting an
appropriate opacity function. Practical and successful real-time 3D ultrasound volume rendering can be achieved in
Obstetrics and Angio applications where setting these opacity functions can be done rapidly, and reliably. Unfortunately,
3D ultrasound volume rendering of soft tissues is a challenging task due to the presence of significant amount of noise
and speckle. Recently, several research groups have shown the feasibility of producing 3D elasticity volume from two
consecutive 3D ultrasound scans. This report describes a novel volume rendering pipeline utilizing elasticity
information. The basic idea is to compute B-mode voxel opacity from the rapidly calculated strain values, which can
also be mixed with conventional gradient based opacity function. We have implemented the volume renderer using GPU
unit, which gives an update rate of 40 volume/sec.
A method to obtain 3D structural measurements of the proximal femur from 2D DXA images and a statistical atlas is
presented. A statistical atlas of a proximal femur was created consisting of both 3D shape and volumetric density
information and then deformably registered to 2D fan-beam DXA images. After the registration process, a series of 3D
structural measurements were taken on QCT-estimates generated by transforming the registered statistical atlas into a
voxel volume. These measurements were compared to the equivalent measurements taken on the actual QCT (ground
truth) associated with the DXA images for each of 20 human cadaveric femora. The methodology and results are
presented to address the potential clinical feasibility of obtaining 3D structural measurements from limited angle DXA
scans and a statistical atlas of the proximal femur in-vivo.