The German MEDARPA consortium, consisting of five
technology and three clinical end user partners, has created the VR/AR
navigation system to solve the surgeon's limited viewing field of the
patient, an ever recurring problem in medical interventions. The
MEDARPA workstation provides spatial registration tools to restore the
missing visual information without obstructing the physician with
complicated technical devices or constructions. As such the surgeon can
"look into" the patient during the operation, without having to take
away his eyes from him. The information is provided on a freely
positionable, half-transparent display, the so-called "virtual window"
and can be used by the surgeon whenever he needs it.
The MEDARPA system can be used, among other applications, in
minimally invasive heart surgery, pneumology and radio-oncology. In
brachytherapy, for instance, irradiation-pillows must be advanced as
close as possible to the patient's tumour to minimize the damage of the
healthy cells surrounding the tumour. After a preceding CT-based
three-dimensional planning of the brachytherapy treatment, the
irradiation is performed with a small radio-active source, inserted
into the irradiation probe by a computer-controlled afterloading
device, right into the tumour itself. Within the tumour, a very high
irradiation dose can be achieved while the surrounding structures as
well as the skin is being preserved.
The MEDARPA AR display is used during the intervention but also in
post-implentation-planning procedures to compare the post-planning
results with the actual probe situation and the isodose processes in
the planning CT. In this way it is possible to exactly determine the
position, to create a complete view as well as to control the
graphic-interactive access of the surgical instruments. The application
of augmented reality allows to overlay the real view on the patient
with the computer-generated images.
In addition to his experience with human anatomy and his good
memory of the previously gathered patient data, the surgeon now can
rely on the interactive visualization capabilities provided by the AR
semi-transparent display. The lack of spatial reference between the a
priori captured data and the position of the patient during the
intervention no longer exists. This is of great value in biopsy
procedures. The surgeon no longer needs to inject the puncture needle
"blindly" with only an accurate planning and his experience at hand to
support him while still running the risk of damaging healthy tissue.
The AR workstation prevents the physician from injuring an embryo
during an amniocentesis, from violating nerve cells in the spinal cord
during a lumbar puncture and from paralyzing the patient by accident.
And then we did not even mention the punctures in the brain area where
important areas could be harmed without the use of a savvy navigation
tool.
The MEDARPA consortium particularly has addressed the medical area
in developing the VR/AR navigation system but the innovative technology
can also be easily adapted to other application domains, in which the
user has little or no opportunity to carry additional devices with him,
such as for example in the service and maintenance area.
The MEDARPA partners are the Fraunhofer-Institut für Graphische
Datenverarbeitung and the Zentrum für Graphische Datenverarbeitung
e.V., both hosted in Darmstadt, as well as MedCom GmbH; the
Gesellschaft für Medizintechnik mbH in Weiterstadt; and the Medical
Innovative Technology GmbH in Bochum. The three hospital partners are
the Klinikum der Johann Wolfgang von Goethe Universität Frankfurt am
Main; the Klinikum Nürnberg; and the Klinikum Offenbach. More
information is available at the Web site of the MEDARPA project.