The maturity of current 3D rendering software in combination with
recent developments in computer vision
techniques enable an exciting range of applications for the visualisation,
measurement and interactive
manipulation of volumetric data, relevant both for diagnostic imaging and
for anatomy. This paper reviews
recent work in this area from the Image Sciences Institute at Utrecht University.
The processes that yield a
useful visual presentation are sequential. After acquisition and before
any visualisation, an essential step is
to prepare the data properly: this field is known as ‘image processing’
or ‘computer vision’ in analogy with
the processing in human vision. Examples will be discussed of modern image
enhancement and denoising
techniques, and the complex process of automatically finding the objects
or regions of interest, i.e.
segmentation. One of the newer and promising methodologies for image analysis
is based on a mathematical
analysis of the human (cortical) visual processing: multiscale image analysis.
After preprocessing the 3D
rendering can be acquired by simulating the ‘ray casting’ in
the computer. New possibilities are presented,
such as the integrated visualisation in one image of (accurately registered)
datasets of the same patient
acquired in different modality scanners. Other examples include colour
coding of functional data such as
SPECT brain perfusion or functional magnetic resonance (MR) data and even
metric data such as skull
thickness on the rendered 3D anatomy from MR or computed tomography (CT).
Optimal use and
perception of 3D visualisation in radiology requires fast display and truly
interactive manipulation facilities.
Modern and increasingly cheaper workstations (<$10000) allow this to
be a reality. It is now possible to manipulate 3D images of 2563
at 15 frames per second interactively, placing virtual reality within reach.
possibilities of modern workstations become increasingly more sophisticated
and versatile. Examples
presented include the automatic detection of the optimal viewing angle
of the neck of aneurysms and the
simulation of the design and placement procedure of intra-abdominal aortic
stents. Such developments,
together with the availability of high-resolution datasets of modern scanners
and data such as from the NIH
Visible Human project, have a dramatic impact on interactive 3D anatomical