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New dynamic
imaging modality
A
n innovative imaging method
(patent pending: US
61/365,801) was developed
at the Department of Biophysics and
Radiation Biology of Semmelweis
University (Budapest, Hungary). This
technology alters existing 2D or 3D
imaging methods to create a
completely new type of image along
with the traditional one. The new
image shows previously inaccessible
information about movements hidden
inside living bodies or objects, opening
countless possibilities in diagnostic
and industrial imaging areas by
providing functional information.
The development is at the
convergence of two priority fields of
Semmelweis University. Building on
the existing pillars of clinical and
fundamental research, the university
has been strongly promoting a spirit
of innovation for the past few years.
The active support of the technology
transfer office has provided
professional assistance to many
scientists working in innovation. As
part of the project, Krisztián Szigeti
and Szabolcs Osváth, inventors of the
new imaging modality, were offered
training courses on patenting, finance
and marketing. The recent foundation
of the Nanobiotechnology and In Vivo
Imaging Center and the fMRI research
projects all show that functional
imaging is also an important focus of
Semmelweis University.
The last decade witnessed a paradigm
shift of medical imaging. A new point
of view has emerged that emphasises
the importance of functional imaging
over mere visualisation of morphology.
An increasing number of multimodal
instruments combine the information
gained by morphological (eg CT, MRI)
and functional (eg SPECT, PET, fMRI)
imaging methods. The physical and
technical basis of the various
functional methods can be very
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Making diagnostic
assessments safer…
the conventional image,
since it is less affected
by motion artefacts.
The new technology
reconstructs two more
images that show the
pointwise errors of the
static and dynamic
images. The two error
images are very important for computer-based
noise reduction and
data analysis. Such
image processing is
fundamental in many
areas like diagnostic
imaging, shape recognition or contraband
detection. The new
technique gives a better
estimation of errors
Fig. 1: X-ray image of the clockwork of an electronic alarm
than present methods
clock made using the new technology, (a) static image, (b)
dynamic image indicating motion, (c) part of the dynamic
because it is based on
image magnified
the measurement of
physical parameters
rather than a priori
different, but all of them visualise
assumptions. Efficient noise handling
processes going on inside the body.
and good image quality are especially
important in the medical practice. A
The new method brought forth at
better estimation of the error of the
Semmelweis University can provide
image helps to optimise radiation
several existing techniques (eg
intensity and the measurement time
electron microscopy, X-ray projection
necessary to get the diagnostic
radiography, X-ray angiography, CT)
information. This, in turn, facilitates
with movement-related functional
avoiding unnecessary patient doses.
information after a minor software
Fig. 1 shows the X-ray image of the
and hardware upgrade.
clockwork of an alarm clock acquired
The new technology provides four
using the new technology. Fig. 1a
images at once without increasing
represents the conventional static
the necessary measurement time or
image of the electronic circuitry and
radiation dose. The most important
the mechanics of the alarm clock.
of these images is a new ‘dynamic’
Fig. 1b shows the dynamic image of
image that represents local motions
the same part of the clock. In this
inside the patient or studied object.
image, the still parts disappear. We
find a new contrast scheme that is
Besides the dynamic image, the new
based on movement. The brightest
technology also reconstructs a ‘static’
green colour indicates the fastest
image very similar to the existing
moving little shaft and the wheel that
conventional images. This static image,
moves the cogged wheels of the
however, is an improved version of
Public Service Review: European Science & Technology: issue 12
profile
medical imaging has been to
decrease the risks of the examination
for the patient. Such risks are related
to the use of contrast materials or
elevated X-ray doses where imaging
is traditionally difficult due to low
contrast between tissues. The new
technology introduces new motionbased contrasts, and also provides
better noise handling. As shown,
these features allow the visualisation
of organs that usually requires either
the use of contrast materials, or CT
examination, which results in higher
X-ray exposure of the patient. The
new method provides both a dynamic
and a static image, as well as their
respective error images using roughly
the same amount of radiation as
conventional images demand.
Fig. 2: X-ray image of the chest of a frog acquired with the new imaging method, (a) static
image, (b) dynamic image indicating internal motions
clock. To show the capabilities of the
new imaging method, part of the
dynamic image is magnified in Fig. 1c.
The colour scale indicating the extent
of movement is also set to more
sensitive level. In this image the
wheels advancing the second, the
minute and the hour fingers are
clearly visible. This example clearly
demonstrates the large dynamic
range of the movements that can be
imaged at the same time: the wheels
moving the second finger move
3,600 times faster than the wheels
moving the hour finger.
Obtaining images with good contrast,
but keeping radiation doses low is a
challenging task of medical imaging.
Enhancing the low contrast between
soft tissues often requires the
administration of contrast agents to
the patient. These chemicals, however,
can trigger unwanted reactions (eg an
allergic response), which constitute
additional risks for the patient. The
dynamic image has new – motion
based – contrast schemes, which can
make contrast materials unnecessary
in several applications. An example is
given in Fig. 2, which visualises the
heart and aorta of a living animal
without using contrast material.
Fig. 2 represents the X-ray image of
the chest of an African clawed frog
(Xenopus laevis). The first image
(Fig. 2a) is the static image. Fig. 2b
shows the dynamic image of the
same part of the animal. The static
image practically only shows the
bones, since frogs have very low soft
tissue contrast. In the second image,
however, we can see the movement
of the heart, the heart valves, the
aorta, and the alveoli of the lung.
Apparently, the throat of the frog also
moves as the animal breathes.
The above technique is expected to
open up new possibilities in industrial,
security and medical applications.
The method is sensitive to nondirectional chaotic movements as
well. It could be used to characterise
the movement of motors, the
explosion of fuel in engines, electric
discharges, spark gaps, or the flow of
fluids around turbine blades or wings.
The main focus of the development
done at Semmelweis University is
medical imaging.
Implementation of the new imaging
method is expected to make diagnostic
imaging safer. The most important goal
of the past few years in X-ray-based
The new imaging method is also
expected to make diagnosis more
efficient, by making accessible
additional functional information not
available up to now. The new imaging
modality is in its infancy. Continued
research at Semmelweis University
aims to optimise the method of
detecting blood flow in capillaries to
advance the diagnosis of cancer,
conditions of the vascular system, or
autoimmune diseases.
Using the new method invented at
Semmelweis University, multimodal
imaging that provides both anatomical
and motion-based functional
information could become routine in
medical diagnosis.
Szabolcs Osváth
Assistant Professor
Department of Biophysics and
Radiation Biology
Semmelweis University
H-1094, Tűzoltó u. 37-47
Budapest
Hungary
Tel: +36 1 459 1500/60224
Fax: +36 1 266 6656
szabolcs.osvath@eok.sote.hu
www.semmelweis-univ.hu
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