Breakfast DINING HALL MITAT EDITORIAL BOARD

Surf and Sand

Scripps

Measuring RF Heating of Implants
Ergin Atalar, Bilkent University, Turkey
Background
A metallic implant in the body may
cause excessive heating if they are
exposed to a electromagnetic field.
Because of this reason, patients with
implant are not allowed in an MRI
scanner. Knowing the exact amount of
heating is critical in determining the
risks associated. Unfortunately, the
heating values reported in the literature
uses conflicting methods and therefore
producing unreliable results. In this
presentation, heating measurement
methods will be discussed.
Material & Methods
In the proposed method, a gel
phantom is prepared with thermal and
electrical properties that are similar to
human tissue properties. The implant
was embedded into this gel. The RF
power is applied for a duration equal to
the average perfusion time constant of
the body. The peak temperature
obtained from the phantom is
measured and normalized with respect
to the SAR value measured from the a
remote location on the same phantom.
Normalized temperature is reported for
the safety index.
Results
Predicted was compared with measured
temperature increase on three rabbits
at various tissue types. Results will be
discussed in the presentation.
Conclusion
We propose a method to predict in
vivo temperature rise when RF heating
is applied. This method was used on
animal to test the accuracy of
prediction technique. We believe that a
measurement technique similar to
proposed in this presentation needs to
be developed as the standard RF safety
measurement technique.
Keywords
MRI Safety, Implants, Implant
Compatibility

MR and CT-Compatible Robotic
Instrument Guiding System
INNOMOTION
Andreas Melzer, INSITE med. & Dept.
of Physical Engineering @ University
of Applied Science Gelsenkirchen,
Germany
Bernd Gutmann, Innomedic GmbH,
Herxheim, Germany
Michael Bock, Deutsches
Krebsforschungszentrum Heidelberg,
Germany
Harald Fischer, Forschungszentrum
Karlsruhe, Germany
Background
MR-guided percutaneous interventions
have been clinically established with
open low field MR systems. As imaging
quality of closed bore scanners is
superior but the access to the patient
limited a fully MR-compatible
assistance system.
Materials and Methods
A CT and MR-compatible assistance
system Innomotion has been developed
by using polymers and ceramic
materials, piezzo electric and
pneumatic drives and opto-electronic
sensors. The robot arm is attached to
an orbital mounted to the MR table and
provides adjustment of a cannula guide
in 6 degrees of freedom within the MRI
scanner. MRI cross-platform
compatibility has been achieved for
1.5 T MR scanner, Magnetom
Symphony, Siemens, Erlangen and 1.0
T Gyroscan NT and 1.5 T Intera
Philips.
Precision of insertion site and
angulations within the transverse plane
have been evaluated for sciatic pain
injections at lumbar ganglia of spinal
nerve roots and neurolysis of the
sympathetic chain ganglia and plexus
coeliacus. MR guided insertions with
22-18 G MR compatible titanium
cannulae (MRI devices DAUM,
Germany) have been conducted.
Cannula insertion was visualized with
fast gradient and spin echo sequences.
Results
Position and orientation of all cannula
insertions were appropriately visualised
on axial MRI images. Precision of
insertion site in axial plane was +/-
1mm (min of 0.5 mm and max of 3
mm). Angular deviation in the
transverse plane of the cannulae shows
+/- 1° with min of 0.5 and max of 3°.
Conclusion
CT and MRI guided cannula insertion
by using a MR-compatible robotic
assist system demonstrates adequate
precision of insertion site and
orientation of the cannula. Cross
platform MRI compatibility can be
achieved by using polymer, ceramics,
pneumatic drives and optoelectronic
sensors
Key words
Image guided Robotics, MRI
compatible Robotic, Interventional
MRI

MR compatible Cardiovascular
Simulator for Training and
Medical Device Testing
Björn Möller, Sentürk Konak, Peter
Bremer, Thomas Bertsch, Andreas
Melzer, INSITE med. & Dept of
Physical engineering University of
Applied Sciences, Gelsenkirchen and
Biophan Europe, Castrop-Rauxel,
Germany
Background
Testing of medical devices under
simulation of cardiovascular procedures
without using living animals requires in
combination with MR imaging
appropriate lacks of blood flow,
pulsation and heart beating like in real.
We have developed a system you are
able to perform device testing and
simulations of interventional
procedures under life-like conditions.
Material & Methods
Physiological pulsatile blood flow and
heart beating has been simulated as well
as the flow through arteries. To
generate this flow we use a type of
pump, two magnetic valves and a
computer interface. The second part of
the system is a model of the body in
which for example a freshly excised
porcine heart that is pneumatically
compressed with a silicon cuff or
vessels can be integrated. Breathing
movements of organs such as liver can
be achieved via hydraulic drive.
Results
The existing System has been tested in
1,0 and 1.5 Tesla MR. The result of
this test is that it is possible with our
simulator to get adequate signal
characteristics under MR imaging.
Conclusion
The aim for the future is to integrate
an ECG triggered heart pressure sleeve
which can be equip with a real heart to
get close to natural physiological
conditions as far as possible. If the
system provides simulate the periodical
pumping of a heart and the inspiration
and expiration thereby the number of
animal experiments can be reduced.
Keywords
MR imaging, MR- capable
cardiovascular simulator

MRI-GUIDED ROBOT FOR
PROSTATE INTERVENTIONS
Dan Stoianovici, Johns Hopkins
Medicine, Baltimore, USA
Alex Patriciu, Johns Hopkins Medicine,
Baltimore, USA
Doru Petrisor, Johns Hopkins
Medicine, Baltimore, USA
Dumitru Mazilu, Johns Hopkins
Medicine, Baltimore, USA
Michael Muntener, Johns Hopkins
Medicine, Baltimore, USA
Louis Kavoussi, Johns Hopkins
Medicine, Baltimore, USA
Background
MRI provides the best visualization of
the prostate and its surrounding
anatomy. The principal limitations to
routine image guided intervention (IGI)
use are the challenging MRI
environment and scanner ergonomics.
Material & Methods
An MRI compatible robot (MrBot) was
developed. The robot is designed for
transperineal percutaneous prostate
interventions, and customized for fully
automated MRI-guided brachytherapy.
With different end-effectors, the robot
applies to other prostate IGI. The
robot is constructed of non-magnetic
and dielectric materials and is
electricity free using pneumatic
actuation and optic sensing. A new
actuator (PneuStep) was developed to
provide easily-controlled, safe, and
precise motion by using a stepping
principle.
Results
The robot fits standard, closed-bore
MRI scanners along the patient. It is
able to stay fully operational during
MR imaging without deteriorating the
quality of the scan. Tests in tissue
mock-ups have shown 0.7 mm (SD
0.36 mm) seed placement errors. The
robot tested without any interference
up to 7T.
Conclusion
The robot presents uncompromised
MRI compatibility by using the first
fully MRI compatible motor. It is
capable of automated, highly accurate
needle placement. Prior to any clinical
use, more extensive testing will be
performed. We believe that the robot
may become a useful IGI instrument.
The PneuStep motor may also allow
for other IGI robots to be developed.
Keywords
MRI, robot, pneumatic, motor,
brachytherapy

Fabrication of Multimodality
Vascular Imaging Phantoms with
Fiducial Makers and Pathological
3D Geometries obtained in CT-
Scan
G. Cloutier, L. Allard, B. Chayer, F.
Tanguay, F. Treyve, Z. Qin, G. Soulez,
University Montreal, Canada

Multimodality vascular flow phantoms
are ideal tools as they provide a way of
testing the geometric accuracy, with
easy reproducibility of the
experimental conditions, when
different imaging methods are
considered. They can also be used to
compare the blood flow velocity
patterns obtained by ultrasound and
magnetic resonance imaging. With the
recent developments in the
manufacturing process of vascular
phantoms, stereolithography combined
with lost-material techniques, rapidly
became the most interesting approach
to create the casting of realistic
vessels. However, even though the
Cerrolow metallic alloy seems the
better choice because of its superior
strength and its ease of removal, metal
residues are frequently left in the lumen
after casting, especially in complex
irregular lumen geometries. This could
cause potentially imaging or flow
artefacts, specifically with MR
imaging. The objective of this study
was to develop a new fabrication
process that allows enough flexibility
to build realistic vessels, that presents a
good geometric accuracy without metal
residues, and that could be used with x-
ray as well as MR and ultrasound. The
geometrical accuracy of the new
melting material used is discussed and
different realistic geometries
mimicking pathological vessels are also
presented. In-stent restenosis models
can also be considered. In conclusion,
this new fabrication process, combined
with the technology that we had
already developed for multimodality
vascular imaging phantoms provides
fiducial markers visible in DSA, CTA,
MRA and ultrasound, and the
fabrication of realistic and accurate
replicas of any pathological vessels.

Roboter-Assisted Biopsy vs. Free-
Hand-Technique using Ultrasound
Guidance: first in-vitro Results
Joachim Kettenbach, Dept of
Radiology, University Hospital,
Vienna, Austria
Gernot Kronreif, PhD, ARC Seibersdorf
Research, Austria
Background
To validate feasibility and accuracy of
robot-assisted biopsy in-vitro
compared to a free-hand technique.
Material & Methods
Peas (diameter 9.9±1.6 mm) embedded
within a gel-phantom were randomly
selected for either robot-assisted biopsy
(n=20) or for biopsy using a free-hand
technique (n=20). For robot-assisted
biopsy positional data of an US
transducer was recorded by an optical
tracking system. For hand-held biopsy,
a biopsy guidance tool was attached to
the US transducer. Only one needle
pass was performed and the length of
the biopsy specimen was measured to
proof efficacy. Abbreviations of the
actual needle tract were evaluated using
ultrasonography.
Results
A successful biopsy was performed in
19/20 biopsies (95%) using the
freehand technique and in 17/20
roboter-assisted biopsies (85%). The
length of the harvested specimens
(mean 4.7±2.6 mm) was not significant
different (p=0.07). The deviation of
the needle tip from target along the z-
axis was not significant (p=.953). The
median intervention time using the
free-hand technique (115.6 sec) was
significant shorter (p<.001) than with
the robot.
Conclusion
Robot-assisted biopsy was feasible and
the length of the biopsy specimens
were equivalent to the free-hand
technique
Keywords
roboter-assisted, ultrasound, biopsy

Development of Minimally
Invasive Ambulatory Pressure
Monitoring System
Chin Kang Lin, University of
California, Los Angeles
Foad Dabiri, Department of
Computer Science, University of
California, Los Angeles Authors share
equal intellectual contribution
David Jea, Department of Electrical
Engineering, University of California,
Los Angeles Authors share equal
intellectual contribution
Majid Sarrafzadeh, Department of
Computer Science, University of
California, Los Angeles
Mani B Srivastava, Department of
Electrical Engineering, University of
California, Los Angeles
Peter G. Schulam, Department of
Urology, University of California, Los
Angeles
Carlo Montemagno, Department of
Bioengineering, University of
California, Los Angeles
Background
Majority of medical practices focus on
localized symptoms rather than
systemic observations and snap shots
rather than continuous monitoring.
The ultimate goal is to enable patients&#x2019;
experiencing peace regarding wellbeing;
and the immediate goal is to
investigate the physiological change
per different lifestyles.
Material & Methods
Our first step is to develop a minimally
invasive implantable pressure sensing
system that monitors long-term
physiological changes in real-time,
specifically, the pressure changes in the
upper urinary tract per degree of
obstruction. Our system integrates
three components: 1) miniaturized
sensor module; 2) implantable sensor
node contains a processing IC, multi-
channel ADC, conditioning circuit and
the battery; and 3) PDA interfaces and
commands these nodes.
Results
Our tether-free system can measure
pressure continuously during natural
movements for 48 hours and
communicate among the implanted
sensor nodes and the remote PDA 20
feet away. The challenges
encountered—1)biocompatible
packaging, 2)transducer drift, 3)power
management, and 4)in vivo signal
transmission—and the solutions
formulated will be presented.
Conclusion
Designed for urological monitoring,
this ambulatory sensor network has
applications in other pressures (e.g.
intracranial). Most importantly, this
step brings us closer to having a
systemic monitor that improves
understanding of human physiology
and compliance management.
Keywords
Sensor Network, Implantable Sensors,
Urological Monitoring

The Effect of Navigational Aids
(virtual fixtures) on the
Performance of a Computer
Generated Navigational Task;
Implications for Virtual
Endoscopic Training Systems.

Bin Zheng, Alex Kuang, Frank
Henningman, Sharam Payandeh, Alan
Lomax, Christine MacKenzie.
Schools of Kinesiology and
Engineering Science, Simon Fraser
University, British Columbia,
CANADA. E-mail: ajlomax@shaw.ca

Virtual fixtures have been shown to
improve performance in virtual
navigational tasks. Graphic and haptic
virtual fixtures were added to a
computer generated navigation task
consisting of manipulating a virtual
object through a maze; the input device
was a Phantom stylus and the maze was
a two story graphical structure designed
in the Virtual Hand Lab. at Simon
Fraser University.

32 subjects underwent 15 training trials
under four conditions; a green graphic
tunnel showing the direct path; or
force fields guiding the most direct
path; or both haptic force fields and
the graphic tunnel; or no virtual
fixtures. After 15 training trials, all
subjects were transferred to five trials
of the same navigation task with no
navigational aids.

The results showed significantly
improved performance in the initial
trials by the haptics and haptics plus
graphic groups when compared to the
graphic only and no virtual fixtures
groups. In contrast, in the transfer
trials, the haptic and haptic plus
graphic groups showed the greatest
deterioration; the best transfer
performance was by the group that
initially learned to navigate the maze
with no virtual fixtures.

These results have implications for the
design of virtual endoscopic navigation
training systems; for example in
angiography, catheter insertion and
teleoperation.

Non-invasive CyberKnife Ablation
John Adler, Stanford University, CA,
USA
Background
Although radiosurgery has
revolutionized treatment of brain
tumours, frame-based targeting is
impractical for fractionating brain
treatments or treating extracranial
lesions. The CyberKnife, was
developed in response to these
limitations
Material & Methods
The CyberKnife is the first
radiosurgical device to incorporate
real-time image-guidance, which is
based on a concept termed x-ray
image-to-image correlation & is
accurate to within 1mm. Since 1994
the Stanford CyberKnife has treated
more than 2200 patients with a
spectrum of conditions involving the
brain, spine, chest and abdomen.
Results
Studies show that CK radiosurgery
provides better outcomes in acoustic
neuroma patients with useful hearing &
a range of tumors that are immediately
adjacent to the optic nerves and
chiasm, and in more than 200 cases, it
proved an effective substitute for
standard open surgical resection. In
addition to neurosurgical disorders,
Cyberkife radiosurgical ablation can
and is being applied to lesions within
the incorporating sensors of chest wall
excursion, the CyberKnife system
precisely and automatically directs the
robot to retarget the radiation beam on
lesions affected by diaphragmatic
movement such as tumors of the lung,
liver and pancreas.
Conclusion
The spatial fidelity afforded by image-
guided guided radiosurgery is redefining
the clinical management of many
benign and malignant lesions & is
likely to replace many common cancer
and other operations in the future.
Keywords
Radiosurgery, CyberKnife

Nocturnal Electrobioimpedance
Volumetric Assessment (NEVA) for
examination of erectile
dysfunction (ED) after
Laparoscopic Radical
Prostatectomy (LRP)
Marcel Hruza, SLK-Klinken Heilbronn,
Germany
Jan Klein, Department of Urology,
SLK-Klinken Heilbronn, Germany
Michael Schulze, Department of
Urology, SLK-Klinken Heilbronn,
Germany
Svetozar Subotic, Department of
Urology, SLK-Klinken Heilbronn,
Germany
Dogu Teber, Department of Urology,
SLK-Klinken Heilbronn, Germany
Jens J. Rassweiler, Department of
Urology, SLK-Klinken Heilbronn,
Germany,
Background
ED is common after LRP. Different
therapeutic options to start
rehabilitation soon after surgery are
available, but there is no standard
procedure to objectivate early
postoperative ED. We study if NEVA
is useful in early postoperative
recording of ED when standardized ED
questionnaires normally used are not
feasible yet.
Material & Methods
The NEVA&#x2122;-Device utilizing electro
bio impedance to study erectile
dysfunction, developed in 1997, was
never used in this context. A group of
15 patients after LRP underwent non-
invasive nocturnal penile tumescence
measurement with NEVA in the first
night after postoperative removal of
the transurethral catheter. Three glue
electrodes were put on basis and tip of
the penis and on the hip, penile length,
cross-sectional area and volume change
were recorded continuously.
Results
In 9 patients (60 %), erections were
recorded, average number of erections
per night was 2.4 (1-5). The average
increase of penile volume was 159 %
(117-248 %; in healthy persons, it is >
200 %). The mean time of recording
was 487 minutes per night (117-663).

Conclusion

First studies proof that erections are demonstrable in an early postoperative stage after LRP, NEVA was feasible. Further studies will show if our goal to use NEVA to divide up patients to the different therapeutic pathways can be reached.

Keywords

Laparoscopy, Nocturnal Penile Tumescence

Potential of Sensor Data
Processing in the Wireless
Biomedical Sensor Nodes
Ilangko Balasingham1,2, Stig Støa2,
Mats Skogholt Hansen2, Tor Audun
Ramstad2
1 Interventional Centre, Rikshospitalet
University Hospital, Oslo, Norway
2 Department of Electronics and
Telecommunications, Norwegian
University of Science & Technology,
Trondheim, Norway

Complex clinical diagnostics and
treatments require use of different
biomedical sensors. The sensors are
typically used for monitoring a number
of parameters such as blood gas,
invasive blood pressures, pulse rate,
temperature, electrocardiogram, etc.
Another example of using biomedical
sensors is for the detection of
ischemia. However, with a few
exceptions, the biomedical sensors are
a single device with a single output.
This means there will be an array of
biomedical sensors needed for
measuring multiple physiological
parameters to facilitate effective
treatment. The individual sensors are
often connected to the monitoring
devices with wires. This may become a
huge problem; the wires can tend to
cause adverse events and can restrict
the mobility of the patient in the
recovery period. Wireless connections
produce digital data, which along with
other digital data may enable novel
clinical as well as logistics applications.

Advanced biomedical sensor network
may consist of several sensor nodes
connected to each other in a complex
manner. It is therefore desired to have
some kind of intelligent signal
processing of the sensor data locally
before transmitting them to a gateway.
A gateway in a patient near
communication scenario can be a
mobile phone. The local processing of
data can be seen as data reduction,
facilitating reduced number of samples
to be sent to a gateway using a wireless
communication protocol. This means
that the life time of the batteries can
be extended significantly as
approximately 50% of the power from
the batteries is used for data
transmission. In an experimental setup
we have used wireless sensor nodes
from Crossbow Inc, San Jose, CA. Each
sensor node contains a few sensors,
connectors from external sensors,
microcontroller, random access
memory, and ZigBee wireless radio
unit. We installed the Tiny OS, a
custom made operating system for
sensor nodes, by the University of
California at Berkeley in the
microcontroller. The Tiny OS enables
easy high level programming interface
on microcontroller. A simple
experiment was conducted using three
sensor nodes in a network. One sensor
node contains Electrocardiogram
(ECG) data, whereas the second
contains invasive Arterial Blood
Pressure (ABP). The third sensor node
functions as a master node
synchronizing and receiving data from
ECG and ABT sensor nodes. A fourth
node is used as a gateway node, which is
connected to a laptop. The data is
transferred via the gateway node to the
laptop. We use a visualization software
by Crossbow Inc to render data from
ECG and ABT sensor nodes on the
laptop.Measures are taken to reduce
the number of bits sent from the
wireless sensor node. Signal forms such
as ECG and ABT are highly correlated
and redundant. This property enables
compression in the form of a
predictive coding scheme. We also
want to monitor changes in a patient&#x2019;s
condition. If there are no changes, a
minimal amount of data to keep the
connection alive would suffice. The
signal processing done between sensor
sampling and transmission has two
goals. Detect changes in the sensed
data and vary the data rates based on
the significance of the sampled
information. The results will be
presented at the conference.

IGSTK: An Open Source Toolkit
for Image-Guided Surgery
Applications
Kevin Cleary, Patrick Cheng,
Georgetown University, Washington
DC, USA
Background
Open source software has tremendous
potential for improving the
productivity of research labs and
enabling the development of new
medical applications. The Image-
Guided Surgery Toolkit (IGSTK) is an
open source, cross platform, software
toolkit. IGSTK integrates the basic
components needed in surgical guidance
applications and provides a common
platform for fast prototyping and
development of robust image-guided
applications. This presentation will
give an overview of the IGSTK
framework and current status of
development followed by an example
needle biopsy application to
demonstrate how to develop an image-
guided application using this toolkit.
This project has been a collaborative
effort between Georgetown University,
Kitware Inc., Atamai Inc., and Arizona
State University. The work is
supported by the National Institute of
Biomedical Imaging and Bioengineering
at the National Institutes of Health.
Keywords
open source, image-guided surgery,
surgical guidance, tracking, state
machine, needle biopsy, application
prototyping

Surf and Sand

Scripps

Mobile Linear Accelerator for
Intraoperative Application (IORT)
Combined with Advanced
Diagnostic Systems
Michael Friebe, Biophan Europe,
Castrop Rauxel, Germany
Don Goer, Intraopmedical, USA
Ernesto Lanzotti, TOMOVATION, Italy
Background
Intraoperative external beam radiation
can provide higher effective
therapeutic doses of irradiation to
regions of malignant areas while dose
limiting structures are surgically
displaced. Diagnostic imaging control
could be advantageous to this
therapeutic application.
Material & Methods
Up to 12MeV self-shielded mobile
intraoperative linear accelerator
(Mobetron, Intraopmedical, Inc.) with
up to 10Gy per minute radiation in
3cm to 10cm radiation areas with
depths of 1cm to 4cm. Applications in
the surgical suite to gastric cancers and
sarcomas, early stage breast and
pancreas, advanced and recurrent
colorectal cancers, mesothelioma and
lung cancers, as well as other cancers.
The device can be moved to the
surgical area so the patient can be
stationary.
Results
Intraoperative beam radiation in
combination with surgical procedures
significantly increase the 5 year
survival rates. Combination with
diagnostic procedures is difficult due to
the weight and size of the equipment
and limited to X-ray fluoroscopy at the
moment.
Conclusion
IORT has proven to be an effective
method for therapeutic radiation
treatment in the operating room. The
method requires intense collaboration
of surgeons, radiation therapists, and
radiation oncologists. Further R&D to
combine with CT or other advanced
diagnostic system could be beneficial.
Keywords
IORT, intraoperative radiation
treatment, external beam radiation

Efficient Medical Device Design
Workshop
Ted Kucklick, Canuflow Inc., Los
Gatos, CA, USA
Background
The Workshop: Good medical device
design is a marriage of good ideas from
clinical practitioners and the
specialized skills of the medical device
designer. What are some of the
practical tools that the R+D engineer
and physician device researcher and
entrepreneur can use to develop and
refine a medical device? This workshop
will outline some of the ways to
develop and prototype a medical
device, and familiarize the attendee
with some of the resources readily
available to them, including rapid
prototyping, medical device materials
and processes, and many other
important topics. About the speaker:
Ted Kucklick is a medical device R+D
designer and entrepreneur with several
years experience in the field, including
work for RITA Medical. Somnus,
Curon, Starion Instruments, Sleep
Solutions, AfX and many others. He is
a member of the IEEE/EMBS, AMI,
and IDSA professional societies, and is
co-founder of Cannuflow,
Incorporated, a company dedicated to
improved devices for arthroscopy. Ted
is inventor on a number of issued and
pending patents, and author of The
Medical Device R&D Handbook
recently published by CRC
Press/Taylor and Francis.

Keywords

medical device design, prototype,
innovation, invention

SeptRx: A new PFO closure
solution

S. Kleshinski, C. Rice and S. Russell
(listed in the programm)

Nitinol Devices & Components, 47533
Westinghouse Drive, Fremont, CA
94539

Background

The market for devices to close the
heart defect patent foramen ovale
(PFO) is heating up based on recent
information linking the presence of a
PFO to severe migraine headaches.
The presence of a PFO has also been
identified as a contributing cause of
cryptogenic stroke. A PFO contributes
to these conditions by providing a
pathway for emboli in the venous
system to directly reach the arterial
system by passing from the right
atrium to the left atrium.

Device Description

Currently marketed percutaneous
devices for closing PFOs are based on
so-called &#x201C;double umbrella&#x201D; designs
adapted from similar devices used to
close atrial and ventricular septal
defects. In contrast, the SeptRx PFO
closure device has been designed from
the beginning to address the unique
anatomical and physiological
challenges of the PFO. The unique
design characteristics of the SeptRx
device are as follows:

· SeptRx directly treats the pocket of
the PFO while minimizing the impact
to the atrial spaces, especially
minimizing the residual material in the
left atrium. SeptRx call this
IntraPocket Occlusion or IPO&#x2122;.

· The internal mesh of the SeptRx
device provides an immediate, reliable
barrier to the conduction of emboli.

· The frame of SeptRx laterally
stretches the pocket of the PFO to
bring the septal tissues into contact and
trigger the body&#x2019;s natural adhesion
response.

· SeptRx is delivered via a low profile
(9 Fr), over-the-wire delivery system
for increased safety and ease-of-use.

SeptRx is highly radiopaque and fully recapturable.

Comparison of Whole-body FDG-
PET/CT and Whole Body MRI at 3 T
for Tumour Staging in Oncology
Ettore Squillaci, Dept of Radiology,
University of Rome Tor Vergata, Italy
Orazio Schillaci, University of Rome
Tor Vergata, Italy
Alberto Nisini, University of Rome Tor
Vergata, University of Rome Tor
Vergata, Italy
Mauro Di Roma, University of Rome
Tor Vergata, University of Rome Tor
Vergata, Italy
Roberta Danieli, University of Rome
Tor Vergata, University of Rome Tor
Vergata, Italy
Giovanni Simonetti, University of
Rome Tor Vergata, University of Rome
Tor Vergata, Italy
Background
To compare the accuracy of PET/CT
with whole-body MRI (WBMR) in
staging different malignant diseases.
Material & Methods
60 consecutive patients with known
primary tumours underwent FDG
PET/CT for tumour staging (GE
Discovery ST 16). Imaging evaluation
was performed for CT alone, PET +
CT viewed side by side, and fused
PET/CT data. WBMR examinations
were performed with a 3T system
(Philips Achieva). A coronal STIR-
sequence was used before and after
administration of 20 ml of GD-DTPA
at 2ml/sec. Histopathology or clinical
follow-up of 6 (+/- 2 ) month served as
standards of reference.
Results
Fused PET/CT proved significantly
more accurate in assessing the overall
TNM stage compared to CT alone
(p<0.05), side-by-side CT + PET
(p<0.05) and WBMR. Of all 60
patients 54 (90 %) were correctly
staged with PET/CT, 42 (70 %) with
side-by-side CT + PET, 38 (63 %) with
CT alone and 36 (60%) with WBMR.
No statistically significant difference
could be detected between PET/CT and
CT + PET in assessing M-staging.
Combined PET/CT had an impact on
the treatment plan in 3 patients
compared to other PET modalities and
with 2 patients compared with WBMR.
Conclusion
Dual-modality is significantly more
accurate than CT alone and side-by-
side CT + PET when staging different
malignant diseases. WBMR is an
effective and fast method for staging
cancer patients but cannot reach
accuracy of FDG-PET/CT.
Keywords
Tumor staging, FDG-PET/CT, whole-
body MRI (WBMR)

Next-Generation Ventricular
Assist Device
Jeff Helfer, MyoTech & Biophan
Technologies, Inc, Henrietta, NY, USA
Background
The acceptance within the medical
community that ventricular assist
devices (VADs) provide many benefits
for heart failure patients has created
substantial interest in this new course
of treatment for heart disease. We
report on a new, minimally invasive
VAD for treating many types of heart
failure. The MYO-VAD consists of a
flexible polymer cup that is installed
around the heart, a drive unit,
performance monitoring system, and
operating algorithms that support the
use of the MYO-VAD as a critical life-
supporting system. Incorporating a
pneumatically activated liner, the
MYO-VAD operates by compressing
and expanding bi-directionally,
providing the energy that allows the
heart to restore the input and output of
blood to life sustaining levels. The
exhausted heart&#x2019;s structure is the
pump; the MYO-VAD simply supplies
the energy to allow it to beat
again.Since only the patient&#x2019;s own
heart tissue contacts their blood, the
MYO-VAD eliminates the many
bleeding, stroke, and infection
complications that plague current
VADs. Unlike existing VADs, the
MYO-VAD provides complete
pumping support (both filling and
emptying of the heart) to both
ventricles. Additionally, the healing
environment created by the MYO-
VAD promises to rehabilitate many
sick hearts, allowing the device to be
removed and the heart to function
properly again without assistance.
Keywords
ventricular assist devices

NEW METHODS OF IMAGING
PROSTATE CANCER BASED ON
ULTRASONIC SPECTRUM
ANALYSIS AND NEURAL-
NETWORK CLASSIFICATION
Shreedevi Dasgupta1, Ernest Feleppa1,
Christopher Porter2, Andrew Kalisz1,
Jeffrey Ketterling1, Fernando Arias-
Mendoza3
1 Riverside Research Institute, New
York, NY, USA
2 Virginia Mason Medical Center,
Seattle, WA, USA
3 Columbia University, New York, NY
USA

No reliable method of imaging prostate
cancer currently exists. Our prostate
tissue-typing studies aim to develop
better methods of imaging cancerous
prostate tissue and as a result, to
improve the effectiveness of biopsy
guidance and treatment monitoring.
Success will reduce the false-negative
rate of biopsies and treatment side-
effects.

Ultrasonic (US) radio-frequency (RF)
echo-signal data, and clinical variables
e.g. prostate-specific antigen (PSA),
were acquired during biopsy
examinations. Spectral data computed
from RF signals using biopsy results as
the gold standard were used to train a
neural-network classifier. The trained
classifier then was used to create a
lookup table that returned cancer-
likelihood scores from computed
spectral parameters and the PSA was
used to generate tissue-type images
(TTIs). Neural-network-based classifier
performance gave an improved ROC-
curve area of 0.844 ± 0.018 compared
to 0.638 ± 0.031 for B-mode based
classification. The sensitivity of
neural-network based classification was
superior to that of B-mode-guided
biopsies. TTIs generated from
examinations of patients scheduled for
prostatectomies showed tumors
entirely unrecognized in conventional
US images and undetected during
surgery.
Our classification methods are being
extended to include magnetic-
resonance spectral (MRS) techniques
that use the choline to citrate ratio to
distinguish cancerous from non-
cancerous prostate tissue. 3-D
renderings of prostatectomy histology,
US images, and MR images show
encouraging correlations, and
combining MRS parameters with US
spectral parameters appears to have
potential to further improve prostate-
cancer imaging.

TTIs based on neural-network
classification of US and clinical
parameters continue to show promise
for improving the detection and
management of prostate cancer.
This research is supported in part by
NIH/NCI grant CA053561.

Monitoring and comparison of
bipolar and monopolar
radiofrequency ablation
Thomas Langø, SINTEF Health
Research, Trondheim, Norway
Yunus Yavuz, St. Olavs Hospital,
Trondheim, Norway
Mine Güngör Güllüolu, Department of
Pathology, Istanbul Medical Faculty,
Istanbul University, Turkey
Brynjulf Ystgaard, St. Olavs Hospital,
Trondheim, Norway
Ronald Mårvik, St. Olavs Hospital,
Trondheim, Norway
Background
Local treatment methods, such as radio
frequency ablation (RFA) have shown
promising results in minimally invasive
treatment of liver tumours. These
methods are based on the introduction
of an ablation device into the tumour,
with the purpose of a homogenous and
complete tissue destruction of the
entire tumour as well as an
approximate one-centimetre
surrounding zone of apparently healthy
liver tissue.
Material & Methods
We have compared a monopolar
system to a bipolar system in ex- and
in-vivo experimental models. We
measured physiological parameters,
monitored temperature development
close to the RF probes, determined
tissue effects from samples post
mortem, and evaluated the effect of
RFA with and without Pringle&#x2019;s
manoeuvre. In addition, we evaluated a
method for monitoring temperature
using raw ultrasound echo signals.
Results
The lesion sizes increased with increasing power setting and increasing
ablation time. The lesion sizes also
seemed to vary due to inhomogeneities
in the liver tissue. The temperature
measurements from ultrasound data
showed that a high frame rate gave
clear and noise-free temperature
images when using the bipolar system.
Conclusion
The simpler geometry of the bipolar
single probe system seems to be more
suitable for temperature monitoring
using ultrasound signal processing.
Keywords
radio frequency ablation, ultrasound,
temperature

Penelope Surgical Instrument
Server
Michael R. Treat, Columbia
University& Robotic Surgical Tech,
Inc.,
New York email mt23@columbia.edu

The PenelopeTM Surgical Instrument
Server is a partly autonomous,
machine-vision guided, robotic surgical
assistant. Penelope uses voice
recognition to respond to the surgeon&#x2019;s
verbal request for an instrument and
hands the instrument to the surgeon
with a robotic arm. Using a visual
capability, the robot locates the
instruments that the surgeon has
finished using and returns them to the
instrument tray.

Overall behavior of Penelope is
controlled by a software &#x201C;cognitive
architecture&#x201D;. The cognitive
architecture contains a rule-based
inference engine and a set of rules.
These rules are essentially IF-THEN
statements. Inputs to the cognitive
architecture come from the robot&#x2019;s
sensory systems such as the visual and
speech recognition systems. Inputs
also come from sensors which monitor
the internal state of the robot, such as
position sensors in the joints of the
arm. When the conditions of an IF
clause of a rule are met, the rule
&#x201C;fires&#x201D;, producing some sort of output
of the robot. Outputs may be motor
actions, speech utterances or internal
&#x201C;assertions&#x201D; that are presented back to
the inference engine for further
consideration. With a fairly large
number of rules, very complex
behavior can be produced, potentially
giving the robot great flexibility to
respond to varying conditions including
off-nominal ones.

The robot&#x2019;s software also includes a
&#x201C;prediction engine&#x201D;. The prediction
engine keeps a simple database about a
surgeon&#x2019;s individual preferences. With
this database, statistical techniques are
used to anticipate the surgeon&#x2019;s
requests for instruments. The more
experience the software has with a
particular surgeon, the better its
predictions become.

The machine-vision system is another
feature of this robot. Machine-vision
identifies and counts surgical
instruments. Machine-vision is an
excellent way to count all of the items
used in surgery including small things
such as surgical sutures and orthopedic
screws.
Penelope is the first of a new type of
autonomous robotic surgical assistant.
These robotic co-workers will improve
the quality, consistency and safety of
surgical care for civilians, soldiers and
space travelers. The National Science
Foundation, the US Army&#x2019;s
Telemedicine and Advanced
Technology Research Center, the
Defense Advanced Research Projects
Agency, the NewYork-Presbyterian
Hospital, and the Department of
Surgery of Columbia University deserve
the credit for making this innovation
happen.

New tools for Endoluminal
Resection of Flat GI Lesions
Alberto Arezzo, Ospedale Evangelico
Internazionale, Italy
Background
Since the beginning of operative
flexible endoscopy the treatment of
large flat polyps of the digestive tract,
defined as a flat lesion >3 cm in
diameter has been controversial.
Material & Methods
In 2001 a new EMR technique was
described using an IT knife from
Olympus, which should allow a better
handling of the lesion to resect. This
technique is today widely used in Japan
to treat large flat lesions of the upper
GI tract. In Western countries we
experience more often the finding of
large colonic lesions and therefore the
new tool is currently tested on the
removal of lower GI tract lesions.
Results
In a non randomized trial we have
matched 24 patients treated by
conventional EMR by lift and cut
technique (group A) and 24 patients
treated with the aid of the IT knife
(group B). In both cases flat lesions
where larger than 3 cm in diameter,
with an average of 4.5 cm. In group A
we collected an average of 4.2 - 1.1
specimens while in group B 4.1 - 1.1
with 10/24 (41%) specimens collected
in a sigle stage. A single case of
perforation treated by clip application
has been reported in both groups. Two
patients in group B were indicated for
surgery after endoscopic removal
attempt, failed for difficult positioning.
Conclusion
EMR with IT knife is an interesting
new chance for flexible Endoscopy. Its
employment anyway is skill
demanding, operator dependent,
difficult to reproduce.
Keywords
Large colonic lesion flexible endoscopy

Surf and Sand

Scripps

THE OR LOGBOOK

Enric LAPORTE, Hospital de Sabadell,
Hospital de Sabadell, Barcelona,
Spain
VILÀ Jordi, Fundació Parc Taulí,
Hospital de Sabadell, Barcelona,
Spain
SALES Bernat, Fundació Parc Taulí,
Hospital de Sabadell, Barcelona,
Spain
Jordi PÉREZ, Hospital de Sabadell,
Hospital de Sabadell, Barcelona,
Spain
Josep PLANELL, Hospital de Sabadell,
Hospital de Sabadell, Barcelona,
Spain
Background
The ability to record and store
information during surgery, should
yield to an increase in the safety rates
in the health environment for both
users and professionals. The OR
logbook is a piece of software designed
specifically for this purpose
Material & Methods
The application is a specific
implementation of a technological
platform (Monsurin).As a whole the
system is built out of three basic
components: a-data grabbing: vital
signals, state of devices and
multiplexed video and audio; b-data
processing: UMDD, video compression
(H.264) and audio, vital signals,
metadata and other parameters,
integration through HL7,and security;
c-storage and transmission of data:
client-server architecture and web
services. HL7 and DICOM
Results
On a computer screen you can see all
of the data and activity information
that occurred in the OR. The interface
is straightforward and intuitive.
Monitoring data is displayed
synchronous with video recorded during
the operation
Conclusion
The scientific value of this platform
will come from the analysis of the
information recorded in an integrated
way. It cannot be underestimated the
value of having access to a huge and
unified database that will be built over
time. Many technology areas are
involved but the IT engineering is
required to design the architecture of
the high performance hardware and
software systems needed to support
such a high demanding solution both in
processing speed and storage terms
Keywords
OR safety-data monitoring and
transmission

HYBRID IMAGING - Emerging
New Imaging Systems
Michael Friebe, TomoSystems &
Biophan Europe, Castrop Rauxel,
Germany
Background
Hybrid imaging is not only PET/CT +
SPECT/CT. HYBRID is something of
mixed origin or something having two
kinds of components that products the
same or similar results. Hybrid systems
could include combinations of many
different imaging systems. This
presentation summarizes current
techniques with a future outlook.
Material & Methods
Not every combination makes sense.
To combine PET or SPECT
(molecular imaging) with CT is
currently the most widely used Hybrid
system. Assumption is that the fusion
of molecular imaging and CT data
acquired sequentially on one device is
clinically superior to side-by-side
evaluation of separately performed
images. To combine MRI+X-ray also
would make a lot of sense. X-ray
reveals hard materials (bones+surgical
tools). However, it cannot image soft
tissues like internal organs and blood
vessels can only be seen with injected
contrast media. MRI reveals intricate
details of soft tissues and vessels but
still does not show tool movement
accurately. X-Ray + MRI complement
each other, but the effects of
magnetism on moving electrons needs
to be overcome.
Results
Hybrid Systems are mainly used for
oncology imaging today. Future
systems will also be used for minimally
invasive procedures. These procedures
reduce trauma, blood loss, and recovery
time for patients. Their success hinges
on novel imaging systems revealing
soft and hard tissues.
Conclusion
Expect to see many more Hybrid
Systems in the near future.
Keywords
Hybrid Imaging, PET/CT, MR/PET,
XMR

How do we construct operating
rooms for treatment of vascular
disease?
Brynjulf Ystgaard, University Hospital,
Trondheim, Norway
Jan Gunnar Skogås, Dept of Medical
Technology, Trondheim, Norway
Johannes Eggen, Arstad Architects Ltd,
Trondheim, Norway
Asbjørn Ødegård, Dept of Radiology,
Trondheim, Norway
Hans Olav Myhre, Dept of Surgery,
Trondheim, Norway
Background
Traditionally, operating rooms are
expensive to build and to run. There is
usually lack of flexibility when new
surgical methods are introduced into
the clinical setting. At St. Olavs
Hospital, University of Trondheim,
where we are building a completely new
hospital, we wanted to focus on
research and development to solve
some of these problems.
Material & Methods
The unit consists of two operating
rooms; one for laparoscopic surgery
and one for endovascular therapy. A
lecture room in the upper floor allows
medical students and specialist
candidates to follow procedures on HD-
screens on a PC.
Results
A part of this project has been to
evaluate what is necessary regarding
separate rooms in the neighbouring
areas of the operating room itself. A
preliminary conclusion is that only the
operating room is absolutely necessary
while other areas including offices etc.
can be replaced.By performing these
architectural changes, we think that it
is possible to save about 20% of the
construction costs for operating rooms
compared to traditional construction.
Conclusion
In the operating room for endovascular
therapy we have integrated an
angiography laboratory with facilities
for open surgery. We feel this is
important because vascular surgeons
and interventional radiologists are to a
greater extent working together in the
treatment of vascular diseases
Keywords
Vascular surgery - Operating rooms

Robotic Platform B-RobII: In vitro
Tests and Results
Gernot Kronreif, Mechatronic
Automation Systems, Austria
Martin Fürst, ARC Seibersdorf
Research GmbH, Austria
Wolfgang Ptacek, ARC Seibersdorf
Research GmbH, Austria
Martin Kornfeld, ARC Seibersdorf
Research GmbH, Austria
Joachim Kettenbach, University
Hospital of Vienna, Austria
Background
A modular automated targeting device
for percutaneous interventions under
US and CT guidance has been
developed. For evaluation of the
system concept and accuracy of needle
positioning a series of in-vitro tests has
been performed. Both robotic system
and test results are described in this
presentation.
Material & Methods
The developed targeting device
consists of one or two 2DOF
positioning modules in different
configurations. Depending on the
chosen configuration the targeting
device allows 2DOF needle angulation
(+/- 30°) and 2DOF positioning (+/- 20
mm) with high accuracy. For system
evaluation different phantom tests
have been developed. Planning of the
intervention is on basis of imaging data
sets - after graphical selection of the
target and manual pre-positioning of
the device, correct angulation is being
set by the robot. Finally the needle is
being inserted manually and the
deviation between target position and
needle tip is measured. Different ways
of registration of the robot into the
coordinate system of the imaging data
have been evaluated.
Results
The developed system is easy-to-use
and does not interfere to the clinical
work-flow. System accuracy and
overall performance is being tested
successfully.
Conclusion
The realized prototype of a modular
automated needle guide allows
positioning of a biopsy needle based on
an intra-operatively planning with high
accuracy.
Keywords
Interventional Radiology; Medical
Robotics; Image Guided Therapy;
Needle Placement