Journal of Computer Aided Surgery Vol.4 No.3-1
Abstract：We have developed many kinds of robots for minimally invasive
neurosurgery．We believe that we could extend the range of the robotic
minimally invasive surgery by developing our system that assures surgical
manipulator system a suitable safety .In this report，Trends of the technoIogies
for minimally invasive surgery would be shown..
Key words：Minimally invasive surgery，Medical Roborics，Manipulator
Abstract
Information－guided robotic surgery，assisted by strategy deskand visualization
of medical information， will be come the next generation of neurosurgical
systems．However，intraoperative real－time decision making supporting
system，ensured an accurate response to trouble，is required for safety
and accuracy surgical procedure. Robotic surgery may help to ensure that
the goals of safety and high quality outcome in neurosurgery.In this article
we describe our constructing strategy desk and our robotic surgery system（open MRI
compatible manipulator and micro－LASER ablation system ）that we are developing．
Keywords：CAD，CAM，advanced hands，strategy；manipulator，micro－LASER
Abstract：Among a variety of congenital malformations，myelomeningocele
has been known to be amenable to in uterorepair in recent years．Currently，fetal
surgery for this doomedanomaly is achieved with the fetus exposed by hysterotomy
because the initial attempts at endoscopic repair were all technically
unsuccessful．To accomplish a fetoscopic repair，we have been trying to
employ a telecontrolled micromanipulator system which was originally developed
for minimally invasive microneurosurgery．Our newly manufactured3D endoscope
which is smallest in the world is supposed quite useful in tailoring this
microneurosurgical system for our purpose．Unlike those patients who underwent
regular surgery，fetuses who should continually stay with in theuterus
postoperatively are hard to monitor using standard devices．We have been
working on an experimental means of physiological or visual fetal monitoring
system．Wireless ultra－micro capsule sensors which can be put subcutaneously
mayeffectively transmit fetal tempetature and ／ or heart rate to receiving
sets outside the mother．Likewise，wireless tiny video cameras left within
the amniotic cavity are expected to continually send outward fetal visual
information to a 3D display monitor．Putting these altogether，fetal repair
for myelomeningocele may be completed fetoscopically contributing much
to the affected infant and mother.
Key words：fetal surgery，myelomeningocele repair，telecontrolled micromanipulator
system，postoperative fetal monitoring，capsule sensor（wireless ultra－micro），video
camera（wireless tiny）
The purpose of application of robotics in vascular surgery is toperform
the surgical procedure less invasively，more safely，and to enable the
procedure which otherwise is considered as impossible．To establish the
therapeutic robotic system for vascular surgery，we have developed several
fundamental technologles．These included visualization of arterial atheroma
by specific monoclonal antibodies，real－time integral videography system，automatic
measurement system of in vivo endothelial function，manipulator with multi－degrees
of freedom，real－time three－dimensional ultrasonography monitorlng system，gene
transduction system by electroporation to introduce plasmid DNA to vascular
wall cells，drug delivery system with drug eluting stent． Although promising，further
studies are indispensable to integrate these fundamental technologles to
established robotic therapeutic system for vascular surgery．
Key words:minimally invasive surgery,therapeutic robotic system,vascular
surgery
Abstract：
The NORIKA Project Team is the development group responsible forthe battery－free
micro capsule endoscope．RF SYSTEM lab's specialization is the
culmination of microwave and CCD camera technologles．Because of the risks
involved with toxic substances from batteries entenring the human body，the
camera is powered wirelessly by microwave energyfrom outside the body.This
system can supply stable power and guarantee imaglng times of much greater
duration than possible with batteries．Concerning image reproduction and
brightness，CCD is a superior device，but its power consumption is high．To
circumvent this character，the DSR whichalmost consumes the total power，is
separated from the CCD outside the human body．Because of the camera's
focusing feature and the intensity of 4 LED lamps that are independently
controlled，clear images can be monitored evenin the darkness inside the
body．Capsule rotation can also be accomplished fbr examination of specific
areas．This rotation mechanism combines 3－pole motor theory with strobe
light technology．The external unit，which transmits data and power，includes
a vest with coils inside and agame system－like controller．
Future developments of NORIKA will include two small compartments for doctors
to use at their discretion．
Keywords:NORIKA,battery-free,capsule endscope,microwave,CCD
Abstract：
SIREMOBIL Iso－C 3D is based on the mobile iso－centric C－arm based X－Ray
Imaging system. In addition to normal 2D imaging，SIREMOBIL Iso－C 3D enables
3D data acquisition and real－time 3D image postprocessing in the operating
room．Operators are able to observe the bone fracture and precise positioning
of the instlements by 3－Dimensional images.Furthermore，the system with
a navigation interface，is possibleto send the 3D data－sets intra－operatively
to a navigation system，without matching or registration procedures．
Abstract：Mimimally invasive surgical procedures under image guidance are
carried out using intraoperative MRI．MRI has been used as image guidance
for minimally invasive thermal ablation because of its unique features
of higher tissue contrastand temperature sensitivity．A double－donut type，open
configuration MR system，which was especially designed for intra－operative
use，enabled us to employ new minimally invasive surgical techniques under
the guidance of MR images．PC based application software was created to
aid guidance by interactive controlling of MR scanning and guidance－visualization．Needle
tracking and temperature mapping are the two phases are required for localizing
the lesion and measure the temperature change during ablation respectively．The
automation of the system and interactive control of the ablation procedure
reduced the procedure time and reduced the operator load．
Keyword：Thermo－coagulation，MR－guidance，Temperature monitoring，Needle
tracking．
Abstract
Temperature imaging with MRI is the only currently－available technique
for mapping temperature distributioninside human body．This work describes
the principle of the temperature imaging method using water proton chemical
shift and introduces some examples of recent progress of this technique．The
temperature dependence of the water proton chemical shift is based on the
fact that theproton resonance frequency strongly depends on the hydrogen
bonding strength．Because the temperature coefficient of the chemical shift
is small（－0・01ppm／oC），the technique significantly suffers from motion
of the target tissue.To over come the motion artifact，in the recent work
for the thermal therapy assistance，precise breath holding with optical
abdomen wall displacement sensor was adopted together with a post processing
algorism based on the finite element method（FEM）.The resultant images
clearly visualized the temperature distributionon the sagittal plane of
the movable organ，liver.The MR temperature imaging technique is expected
to be a great clinical tool for any of thermal therapy procedure，although
the quantitative analysis of the technique has to be further performed.
Keywords temperature，MRI，water，proton，chemical shift，resonance frequency，phase
Abstract．
The CyberKnife is an image－guided robotic system designed forstereotactic
radiosurgery．This system uses a lightweight，x－band linear accelerator，computer-controlled
robotic arm，a pair of orthogonal x－ray imagers（TLS：Target Locating
System），and a computer workstation．During the treatment，the TLS determines
the location of the lesion and communicates these coordinates to the robot．The
robot adjusts the position of the beam to the target．The accuracy of this
system is 0．7mm（median）at Osaka University． The CyberKnife system
offers new options for radiosurgery／therapy．The fraameless nature of
CyberKnife allows tumors in the chest and abdomen to be treated as well.Tumors
in the lower spine，pancreas，and lung have already been treated in theUSA． At
Osaka University we started the real time tracking radiotherapy from November
2001．The real time tracking system option enables one to treat tumorsthat
move with respiration，such as lesions in lung．By this method complications
made by radiation will be suppose to be decreased． A description of the
components，accuracy，and future of the CyberKnife will be presented．
Keyword：Stereotactic Radiotherapy，Robotic，CyberKnife，Tracking
Medical ultrasound imaging is widely used for supporting surgery and
therapy due to its merits；non－invasive， real－time measurement，compact
and easy system to operate． Many techniques of ultrasound－guided surgery and
therapy have been developed for different types of operations，thatis，invasive，interventional，low－invasive methods
such as intraoperative ultrasonography，ultrasound－guided endoscopic surgery，ultrasound－guided
PEIT（percutaneous ethanol injection therapy）and RFA（radiofrequency
ablation）.Here，their outlines are and prospects are described．
KEYWORDS：Ultrasound－guided surgery and therapy，1ntraoperative ultrasonography，ultrasound－guided
endoscopic surgery，ultrasound－guided coagulationtherapy
Abstract：Navigation system has emerged as a heavyweight in neurosurgery. Recently，the advancement of intraoperative imaging contributed to solve the problem of the major error－“brain shift”－in the conventional navigation by using updated images（update navigation）．However，the display of the
navigation is still 2 dimensional images and surgeons should reconstruct
images for reflecting on the real surgical field．We here report the development
of 3－D navigation system updated with intraoperative MRI and itsinitial
experiences．The 30 frames persecond of frame rate was sufficient for catching
up the surgical procedures and 3－D display and the function of“virtual
needle”were helpful for surgeons to comprehend residual tumor size and
location intuitively．In conclusion，the 3－D navigation system is useful
for minimally invasive neurosurgery．
Keywords：update navigation，intraoprative MRI，three dimensional recontruction
Abstract
We have developed advanced technologles such as a surglcal navigation
system to support surglcal operation by utilizing the various infbrmation
obtained pre－andintraoperatively We introduced an open MRI system（AIRIS
II， Hitachi Medical Co.）into an operating theater connected to high speed
computer network and a medical database・The theater was designed to realize
the operation environment in the 21st century，and named the intelligent
operating theater.Up to now，brain surglcal operation was carried out for
140 patients．Although the open MRI system has been used for diagnostic
use in other hospitals，the intraoperative use dramatically lmproved the
clinical results．The 5－gauss line is so narrow that it hardly disturbed
the operation. In addition，this intelligent operating theater was also
useful for the practical evaluation of the medical devices and instruments
under development.
Key words : open MRI，brain surgery，evaluation
Abstract：In order to develop a new perioperative myocardial ischemia monitor
in theOpenMRI－equipped operating theater，the validity for sensing ofthe
chest surface vibration induced by heartbeats was examined．A capacitive
acceleration sensor was attached to the clinical heart sound observation
points and the maximum vibrating point．Eight healthy male volunteers joined
the measurement．Typical wavefbrms had a 12Hz vibration synchronized with
R wave of electrocardiogram.Duration of the vibration was 0．25±0・02
seconds．Cheat scanning by MRI showed the relation between thicknesses
of muscle，fat and amplitude of the acceleration．Current study showed
the possibility for measuring the heart beats conditions and the one of
reasons for the diffbrent amplitudes of acceleration.
Keywords：Perioperative myocardial ischemia，OpenMRI，Acceleration sensor
Abstract：Recently，in Shiga University of Medical Science，liver tumors
are treated with MR－guided microwave ablation using a vertically oriented
MR system，0．5T GE Signa SP／i．This procedure contributes to minimally
invasive surgery .However，Since this method is nowin progress，development
of new MRI compatible device is strongly required．Then we propose a new
concept of surgery assisting mechanism for supporting liver tumor surgical
treatment in safety under open MR device．This assist is designed such
that mechanical safety for liver can be ensured．We aim to shbrten the
treatment time utilizing the proposed mechanism．
Keywords：Surgery assisting mechanism，Safety，MR－guided surgery，Open MRI
Abstract: In this work，we have developed a testbed for the grid assisted
surgery．The grid is a novel infras，tructure that provides anaccess to
shared high perfor－mance computing resources on the Internet.This paper
describes the testbed，a remote parallel computing system for intraoperative
medical imaging. Our current system provides a simulation for the range
of motion adjustment in total hip replacement surgery．To achieve such
high－quality medical imaging in interactive.we have parallelized the compute－intensive
simulation on a PC cluster composed of 128 processors．Acceleration techniques
such as dynamic load－balancing and data－compressing have been incorporated
into the system．Our system also provides remote computing services With
a secure network．The experimental results show that our parallel testbed
accelerates the simulation that take an hour on a single system in less
than a minute and thereby achieves intraoperative planning without dropping
the simulation accuracy．
Keywords Parallel Processing，Collision Detection，Cluster Computing，Computational
Grid．
Abstract－The study on the integration of Image Management System（IMS）and
Tele－Communication System（TCS）started because it is desired to manage
all of the images used by surgery and simultaneously share those with
medical specialists at remote environment．IMS enabled surgeon to manage
eight medical images and operate under real－time image of 30［fps］on
his own selecting.While，by TCS，surgeon can communicate with a medical
specialist and operate under precise indication by directly writing something
on a shared image between operating room and remote environment．On integrating
of two subsystems，by using Common Object Request Broker Architecture（CORBA），existing
subsystem can be integrated regardless of their hardware，operating system
and programming language with minimum engineering overhead but maximum
flexibility and performance．Performance mesurement results for frame－rate
showed that frame－rate was 30［fps］about IMS but 10［fps］about TCS
on local area network.Next step,we will apply this display system to clinical application．
Key Words：Image Management，Tele－Communication，Integration
［Abstract］
We developed a prototype intelligent laser system for Neurosurgery．A tumor
can be enucleated mimimal invasively and highly precisely is have an influence
on probability of patient survival over 5 years．Therefore it is necessary
for the real－time monitoring systems during theoperation，such as MRI
data is reflected in an operation instantly．It is important for this real－time
monitoring during the operation is invisible clearly and reduced a rest
part of a tumor as much as possible．The purpose of this laser system is
to ablate a tumor of a left－thing portion by laser irradiation efnciently．We
reportedthat developed a short－pulse and a high－power laser system（SHG
laser system）having performance with high－ablation and hemostasis ability．
［KeyWord］In elligent laser system，Minimal invasive surgery，SHG laser
system
Abstract: We have evaluated the efficiency of cryptography to develop securetele－mentoring system
in gastrointestinal surgery．Time to transfer a file of 10 mega byte over
Virtual Private Network（VPN）was checked as an index of the efficiency．
In the C4S crypto－system with 512 bit key，it took 1.195±0．017 sec，While
it took 1．031±0．013for transference without cryptography．For cryptogram
of Data Encryption Standard（DES），Triple DES，Rijndael， BlowFish，and
CAST，it took 1．417±0．036，2．600±0．122，1．399±0．032，1．359±0．113，and 2．611±0．118（sec），respectively．The
key lengths of the cryptography systems are 56，168， 128，168，and 128，reSpeCtively．VPN
using C4S was proved to be a secure and fast cryptosystem．It may
play an important role in network system in the fields of tele－medicine， which
requires highly secured communication of patients’ medical information．
Keywords：C4S，Chaos，Tele－mentoring，Security，Cryptography，Virtual Private Network（VPN）
Abstract：In the treatment of the neurosurgery such as encephaloma，it
is very important to remove the tumor accurately at the boundary section
of the tumor and the normaltissue in order to prevent the recurrence of cancer．To
achieve this accurate removal of the tumor，we haveproposed a new treatment
method using the 5 Aminolevulinic Acid（5－ALA）and a micro laser of the
wave length 2．8［μm］.In this method，the tumor fluoresced by 5－ALA
was cauterized by the microlaser．Becausethe micro laser has focal length，it
is necessary to maintain the distance between the laser probeand the target．In
this research，we developed the automatic focusing mechanism using two－guide
laser and a CCD camera．Inaddition，we performed a focusing accuracy evaluation
experiment and the irradiating experiment for a brain of pig．As result
of the experiments，the focusing accuracy waS within 0．5［mm］and possibility
of the clinical application was shown．
KeyWords：Neurosurgical laser，Automatic focusing，Medical robot
Abstract：In this paper，a laser etching method on brain tumors is described．It
has been considered that the precise recognition of the location of malignant
brain tumors by certain monitoring system and the realization of accurate
removal is most important to make advantage of survival rate．Micro－laser（λ＝2．8，μ
m）is characterized by the performance of less invasive treatment because
this wavelength is in absorption peak of water，It is considered that the
micro－laser is suitable for removing the brain tumors in comparing with
any other laser devices.From our resent experiment，the micro－laser could
successfully etch the pig brain surface by ablation process with less damage．
Keywords：λ＝2・8μm，micro－laser,brain tumor，laser etching
【Abstract】For high removal rate of a brain tumor resection，itis important
to get functional information of nervous system accurately and speedy during
an operation as well as anatomical inbrmation by magnetic resonance imaging
obtained preoperatively.We developed a switching circuit for bipolar forceps，being
commonly used，combining to an electric stimulator，which enables functional
mapping and motor，evoked potentials（MEPs）and an oscilloscope，which
elicits somatosensory evoked potentials（SEPs）． We could get reproducible
MEPs from pig limbs by cortical stimulation with the forceps.In gliobrastoma
subjects，functional mapping of awake craniotomy was carried out by cortical stimulation
and median nerve SEPs with high signal and noise ratio were cortically
elicited from the bipolar forceps put on the sensory cortex of generally
anesthetized patients. The system integrated existing equipment into
one device utilized by an operator brings smooth operation and functional
monitoring which had not been able to access to loci by usual probe.
【KEYWORDS】 bipolar forceps，intraoperative monitoring，functional mapping，SEP,MEP,brain
tumor，resection
Abstract：We improved drive performance of safety active catheter of micro
hydraulic drive and developed clinical model．And we developed high performance
pressure control device and verined validity of this model by insertion
test in blood
Keywords：Active catheter，Hydraulic actuator，Band pass valve，Minimally
invasive surgery，Non－invasive inspection
Abstract：A new robotic system named“HyperFinger”for minimally invasive
surgery in deep organs has been developed． The finger size of the latest
version is 10mm and the entire system is much smaller and lighter，and
can be set upon a camera tripod．This is one of the smallest master－slave
robots in medicine．Each finger has seven degrees of freed m and several
unique mechanisms are employed to solve the fundamental issues of conventional
wire drive manipulators．The new concept and system were verified successfully
byin－vivo remote minimally invasive surgery．
Key words：Hyper Finger，Laparoscopic Surgery，Minimally invasive Surgery，Medical Robotics
Abstract
Previously developed three-dimensional (3-D) endoscope system has not become
popular because of its poor resolution and practicabirity . We present
a ew practical 3-D endoscope system for endoscopic surgery.The developed
endoscope,11mm in diameter and 385 mm in length ,had two lenses and two
micro CCD cameras. The weight of the edoscope was 120g and narrow conversion
angle and new lens and digital RGB method improved the brightness,resolution
,and true color reproduction. The developed 3-D endoscope system is a practical
instrument for minimally invasive surgery.
Keywords : Three dimensional endoscope ,binocular,and stereopsis
Abstract:We present a new endoscopic system that provides two different
views simultaneously，one is a wide view（120 degrees）and the other is
an enlarged view with image－shifting mechanism.The system have one optical
view pipe inserted into the body and have one Porro prism（II），which
is used to shift the enlarged view vertically and horizontally，out of
the body．With this endoscope，surgeons can observe throughout the surglcal field
without moving or rotating the endoscope itself
keyword：endoscope，image－Shift，dual－view
[Abstract］We conducted experiments to confirm the quauty of imageof wide－angle view endoscope，and the experimental resuits were good.We developed new algorithms for manipulation of wide－angle new endoscope．Simulation had demonstrated and it had been cleared that our new algorithm is efficient in controlling the wide－angle view endoscope．At the last，the actual endoscope was moved by this algorithm and it worked well though it leaves some problems．
Keywords：Endoscope，Minimally invasive surgery，Wedge prism，Medicalrobots
Abstract：We have developed a three－dimepsional（3D）endoscopic ultrasound
system（EUS）with convex scanning echoendoscope for navigation of endoscopic
puncture．We use an optical tracking system or an electromagnetic tracking
system to detect the position of the probe inside the body．To allot these
positions to two－dimensional（2D）images，our system can reconstruct and
visualize a 3D image in real－time．To display the position of the 2D image
that is scanning with reconstructed 3D image and Computer Graphics images
of the probe and the needle，the operator could detect the position of
the puncture，including peripheral information．We report functions of
our system and experimental studies for navigation system．
Keywords：3D endoscopic ultrasound，navigation，real－time imaging．
Abstract
We developed a new real－time three－dimensional endoscopic ultrasonography（EUS）using
convex scan type echoendoscope.In this study，we evaluated and validated
clinicalapplication of the system in the hepato－pancreato－biliary area．Volume
data of the system were reconstructed by spatially replacing a series of
two－dimensional images corresponding to the position of the ultrasound
probe during scanning．The position of the
ultrasound probe was captured by an electro－magnetic tracking sensor，which
was attached to the tip of the scope．The results of this study demonstrated
clinical applicability of this system．We believe that this system will
improve reproducibility and consistency of the EUS examination．
KeyWords：Endocopic ultrasongraphy，Hepato－pancreato－biliary area，three－dimensional image
Astract：Laparoscopic surgery forces surgeons to operate with mechanical
and visualcon－straints.Surgeons are rpquired to intuit a sense of orientation
in the abdominal cavity solely from the memorized anatomical structure．Laparoscopic
surgery would be technologically improved if surgeons were provided with
the 3D shape of the internal geometry including with texture inforrmation
in an intuitive manner.In this paper，intraoperative real－time 3D visualization
and Data－Fusion using this geometry verifies the functionality in an in－vivo
experiment．
KeyWbrds：Data Fusion，Intraoperative geometry，Registration，Video－based rendering
This paper describes the usefulness of 3D－Magnetic Resonance Cholangiopancreatography
and virtual endoscopy for intraductal papillary mucinous tumors（IPMT）of
the pancreas. We generated surface－rendered virtual endoscopic images
by reconstructing cross－sectional MRI data of 18 patients with intraductal
papillary mucinous tumors（24 lesions）.Ten patients with IPMT underwent
surgical resection，and 7 of them were organ－preserving partial pancreatic
resection．Virtual endoscopy could show inner images of 92％ of the cystic
tumors.The communication between the tumor and the pancreatic ducts was
seen in 77％ of the lesions. The surfaces of intraductal papillary mucinous
adenocarcinoma were displayed as being more
irregular than those ofintraductal papillary mucinous adenoma.In conclusion，virtual
endoscopy showed the communication between the cystic tumor and the pancreatic
ducts and was useful for surgical planning of partial pancreatic resectio.
Keywords：virtual endoscopy，pancreatic resection．
［Abstract］
We described the utility of life－size model of pelvis fabricated by polyurethane
milling machine(Endoplan R)in the surgical decision making for locally
recurrent rectal cancer All patients underwent multi－detector helical
CT of the abdomen and pelvis with contrast media．The contours of bony
tlssues and large vessels of each CT slice were traced automatically by
the computer． Thecontours of intra－pelvic organs and recurrent tumors
were traced manually．The data of model contours were sent to the milling
machine and the polyurethane block was milled．Case No．1：54－ year－old
female．Local recurrence was diagnosed by CT．The life－size model indicatedt
hat resection through posteriorapproach was possible．Local resection
with the excision of the coccyx and the posterior wall of uterus was performed
and curative operation was completed as we had planned．Conclusions： The 3－D
model fabricated by Endoplan R was useful in the surgical decision making
for locally recurrent rectal cancer．
KeyWords：rectal cance,life size model，Endoplan
［Abstract］
Background Selecting the appropriate graft size,and understanding the anatomy of door's
hepatic vessels and bile ducts are the very important aspects of a successful
liver transplantation.the aim of this study was to clarfy the utilityof
three-dimensional computed tomography（3D-CT）in LDLT.
Methods
（Method-1）3D-CT volumetry was applied to 41 donors who underwent hepatectomy
for LDLT,which consisted of an extended left lobectomy in 27，an extended
left lateral segmentectomy in 3, and a right lobectomy in 11．3D-CT volumetry
was performed using the workstation "ZIOM900"（Zio Software Inc.,Tokyo，Japan).The
estimated volume of the grafts in 2D and 3D images were compared and an
error ratio was caluculated.
（Method-2) The questionnaire of whether which 2D and 3D image was more
useful to understand the anatomy of donor's hepatic vessels and bile ducts
was done.
Results 1．The error ratio was 11.7±1．6（％）in 3D，compared with 16．9 ±1.8（％）in
2D. As such,3D-CT volumeery appears to be more exact than conventional
2D-CT volumetry.
2.3D－CT images were more useful to understand the anatomy of donor's hepatic
vessels and bile ducts.
Conclusions 3D-CT is useful for the preoperative simulation in LDLT.
Key Words：Volumetry,visulization,preoperative simulation
【Abstract】
In informed consent of gastroenterological surgery，it is often difficult
for patients to understand explanation if it is only oral or with medical
data.Therefore， we have been developing 3－D animation for informed consent
of gastric surgery for patients to understand easily.We have been
developing 3－D animation of ①diagnosis of gastric cancer（structure of
gastric wall and depth of cancer），②resection and reconstruction of gasstrointestinal
tract，③body image after surgery（wound and drain）.For the patients，it
is easier to under stand methodof surgery，width and depth of cancer，and
body image after surgery．
Keyword：3－D animation，gastriccancer，informed consent
Purpose：Recently，it has been controversial whetherlesion size of osteonecrosis of the femoral head reduce or not in early stage on MRI．So，we need to register the MRI scans and compare lesions in the same planes.The purpose of this study is to address the accuracy of 3D image registration for the proximal femur using a phantom and adequate condition of MRI scan．Material and methods：A phantom with markers attached to the femoral
head was scanned in various positions and all scans were registered to the reftrence scan．The root mean square（RMS）distance between the corresponding marker sets was calculated and translation and rotation error between the coordinate systems defined markers was calculated．Results：The average RMS distance over the femoral head was 0．51±0．18mm，that is sub－voxel size．the mean absolute translation error was 0．56±0．47mm，and the mean absolute rotation error was 0・21±0・23° Condusion：The registration accuracy was near perfect in the phantom study.Its use in the detection of changes in osteonecrosis warrants future evaluation．
Keywords：magnetic resonance imaging；image registration；osteonecrosis
of femoral head
Abstract：
The registration between the femur and the plevis of the preoperative image
and those of the postoperative image is quite useful．But there is too
much artifact because of the implant．In this paper，we evaluate the effect
of the implant，so we compared the cases when the implant is got out from
the postoperative image，or not．As a result，if the implant wasn’t removed，the
registaration failed．But if it was removed，the error of translation was
about 1 mm and the error of the rotation was about 1 degree．We found that
the result of the registration is accurate in the case when the implant
regions are removed．We show that this method is useful in crinical case．
Keywords：volume registration，morphologlcal operation，artifact，corelation
coeffficient
Abstract:We estimate accuracy of the navigation system for hip joint surgery
that we developed［1］．the estimated accuracy of our system is about 1mm
and 1degree，We proved it have an accuracy for clinical use．We can easily
discuss the structure of system and estimate that accuracy， by using extended
registration graph［2］．
Keywords：accuraccy,error propagation，navigation system
Abstract：Uni－compartmental knee arthroplasty（UKA）has many advantages
over total knee arthroplasty（TKA）in better range of motion，less invasiveness
and faster rehabilitation. However，the reported survival rate of UKA has
been lower than that of TKA．This is mainly due to inadequate patient selection
and technical difficulty，especially in the tibial bone cut through minimum
invasive technique.For satisfactory results in UKA，precise positioning
of the tibial component is essential．We have developed a Computer Assisted
Minimum Invasive Surgery System for UKA（CAMISS-UKA），and the purpose
of this paper is to evaluate the accuracy of this system．5 sham bones
、were operated by GAMISS and actual bone cut level was compared with ideal
level in each sham bone．The ideal bone cut level planned in the reconstructed
3D image was replicated in the actual bone cut precisely with CAMISS.The
advantage of this system is that expensive equipment such as optical camera
or 3－D position sensor unit are not necessary．In the current system，genetic
algorithm（GA）was used to match CT images and plane radiographs，which
provide more accurate andreproducible matching.
Keywords；UKA，computer navigation，knee replacement
Abstract: Image guided spine surgery is gradually spread with theadvancement
of pre－surgical simulations from X－ray CT or MR images to realize minimally
invasive and safer surgery．Especially，in vertebrae cervical bone fixation
surgery,the high positioning accuracy is required to avoid injuring dura
mater spinalits and major blood vessels inside the vertebrae cervical bone
during the drilling．However，when using the image guided navigation system，we
encounter the difficulties to have an accurate”registration”between the
navliation results and the device such as needle，screws and drills，because
of surgeon’s tremor and the complicate spatial orientation relations.
To solve these problems，we developed the1St prototype of a simple robot
that has only2 DOF，to navigate the orientation of the device．In this
paper，a newly user interface device with force sensor attached directly
to the robot and 3D visualization system are described．
Keywords：Surgical navigation，medical robot，user interface
Abstract：Anatomical compatibility is important for development of implantable
Artincial Heart．To reduce the kink of the vascular tissue connected
to Artincial Heart and the pressure of surrounding organs，we are develpping
a surgical planning and navigation system for heart transplantation．In
this study，we designed a optical marker for the navigation，which was
appended on our Total Artificial Heart（TAH），and tracked the position
and attitude of
TAH inside thorax．Since the thorax is deep and narrow，the marker was
fixed on TAH by a suction cup to achieve smooth removal and saving size．In
addition，the infrared reflection balls were attached on a long branch
to locate them outside thorax，whose size was optimized with computer
graphic models of thoracic anatomy．The further investigation is ongoing
about the stiffness of the marker fixation，the accuracy of measurement．
Keywords：artificial heart，transplantation，anatomical compatibility，surgical
navigation
Abstract：In the last decades，5－Aminolaevulinic Acid（5－ALA）is used
as exogenous marker for the detection and the diagnosis of the tumor.5－ALA
localizes at thetumor lesions and induces Protoporphyrin IX（PpIX）．PpIX
has property that is excited by UV light and emit a red fluorescence.By
detecting that fluorescence，we can detect the tumor lcation．But there
are many autofluorescence in biological tissue by nature,and become back
ground noise.To slove this problem,wWe have tried to distinguish the fluo－rescence
of PpIX from the autofluorescence by the technique called "Rank Annihilation
Factor Analysis”. To collect the data for Rank Annihilation Factor Anayisis，we
try to excite and detect the PpIX at the multiple wavelength．
Keywords：5－ALA，PpIX，RAFA，autofluorescence，multiple wavelength excitation／detection
Abstract：In order to achieve a perfect removal of brain tumor，navigation
software，which will enhance a reliability of the total function of"Open
MRI”system，has been developed．This navigation system has an optical
measurement apparatus，which can measure a distance between MRI compatible
markers attached onto the patient's bone．As the previous software could
be expressed only 2D images，aspecial skill was required to reconstruct
3D image.On the other hand，our currentf of software includes a 3D viewing
function．Therefore it became possible to reduce a searching duration of
the markers from 20 minutes to 5 minutes.
Keywords：Intraoperative Open MRI，navigation，registration，marker
Abstract：Radiofrequency Ablation（RFA），using ultrasound guidance to insert an electrode delivering radiowaves and ablate the tumor，is generally being performed as a liver neoplasm therapic procedure these days．In dealing with large or plural tumors，RFA electrode needles are inserted more than twice for their limitation of their ablation range，which often leads to the recurrence of incompletely ablated tumors．In these cases，microbubblesmadeinthe nrstablation，Whichbehave as artifactsintheultrasoundimages，CanPreVentthe successive insertions of electrode needles from being inserted correctly．Therefore we propose the development of a navigation system for RFA based on computer，which reflects the demands that inputs to punctuate the target correctly．The system mainly consists of three－dimensional optical tracking device to get the information about the position and the posture of the inserted electrode needle and a personal computer to provide navlgating information to the surgeons．This system provides the operators the flexibility and correctness in RFA．
Abstract
We have reported the usefulness of intraoperative ultrasonographic（US）navigation using 3－dimensional（3D）echoic image under laparoscopy．We，herein，developed new－type probes for tumor ablation including 1）type－Ⅰ，which has only one hole，2）type－II，which has three different angle hole and 3）type-III，which has slit－type hole． Type－II and－III probes are easier to insert a needle for ablation than type－Ⅰ．We performed laparoscopic ablation surgery safely and smoothly using type－II and－III．New type echo probes were useful to make a safe and accurate ablation for liver tumor under laparo－and／or thoracoscopy．
＜keyword＞laparoscopy，thoracoscopy，ablation，navigation，US
Abstract：We have already experienced more than 100 clinical cases of MR－guided
microwave thermocoagulation therapy of the liver tumor．Microwave does
not cause electromagnetic interference in MRI．One disadvantage，however，is
that the size of thermocogulation by microwave is smaller than that by
RF．
For the treatment of bigger tumors，repeated punctures and ablations are necessary．To record and show the coagulated areas，we developed a “Foot Printing”function．A 0．5T GE SIGNA SP／i was used．3 DSlicer was obtained from Brigham ＆ Women’s Hospital to utilize for real time MR image navigation．The“Foot Printing”function was incorporated into the 3D Slicer．The size of coagulated area with 3－minutes microwave ablation is approximately 20x20x30 mm．The“Foot Printing”function could record and show such foot－ball shaped coagulated areas in the 3D volume data．Their locations and sizes could be adjusted manually when necessary．Usually，coagulated areas can not be detected in MRI during the procedure and are evaluated only by a dymamic study at the end of the procedure．Surgeons were required to remember whichparts had already been ablated and which parts should be ablated．The“Foot Printing”function enabled more accurate and sufficient treatment．
Abstract：In our open MR system，an interactive scan plane control system
is integrated and surgeons can control image planes，which include the
path of the puncture needle．We have developedan external computer control
system for our MR scanner．It couldalternately change two perpendicular
image planes，both of whichincluded the path of the needle．It could also
reconstruct 2 images in the corresponding 2 planes of real－timeimages
using the high resolution 3－dimensional volume data acquired just before
the procedure．Totally,4 images in the 2 perpendicular planes（real－time
and re－sliced images）were combined in one display and sent to the surgeons.Since
2－dimensional MR images were used in the MR－guided interventional procedures，the
observations of images in one plane were not sufficient for the accurate
recognition of the location in the 3－dimensional space．This system was
quite helpful for accurate image guidance in the 3－dimensional space.
Keywords：MR－guided intervention，image navigation，scan plane control，computer
assisted surgery
Abstract：This paper suggests an ultrasound guided needle insertion instrument
which can track target motion in real－time．Under traditional ultrasound－guided
needle insertion theraples，surgeons have had much burden to find out the
precise targeting position，particularly when the organ is moving due to
the respiration or heartbeat．We developed a new needle insertion instrtment
which can track moving target based on visual servo control．The prpposed
system could track a moving phantom successfully at speed of 3 frames／sec
processlng．
Keywords：image－guided surgery，needle insertion，motion adaptable，visual servo control
【Abstract】
A CT－based navigation system was used to resect an osteoid osteoma in the pelvis through a minimum invasive approach．The nidus had a 9mm of the maximum diameter and existed in the lateral cortex of the ileum at lOmm proximal from the hip joint．Preoperative planning was made using surface models of the tumor，pelvis，femur，muscles，and skin．Surface registration was done by a needle with LEDs which was introduced percutaneously.The tumor was successfully resected．The CT-based navigation system helped surgeons to observe the nidus directly and it was easy to removethe tumor in a minimum invasive approach．
【Keywords】osteoid osteoma，computer tomography，navigation，minimum invasive
Abstract：We tried to perform a tele－surgery using the network which had connected between Osaka university hospital and Kawasaki hospital．The distance between two hospitalsis 50km．The aspiration of a symptomatic ganglion adjacent to the hip minimalinvasively succeeded with assisted by some advises from a medical specialist in Osaka university hospital using 3 dimensional computer graphics．This network system was practicalin this trialcase．
Abstract：This study reports the technical basis ofimage processing for simulating incision and excision in left ventricular plastic surgery．The images are built on the basis of patient's high－speed cardiac cine CT－images．This is combined with the training system for cardiac muscle palpation necessary to make a surgical plan．A haptic－device corresponding to the movement ofsurgical knives and forceps will be linked with the incision and excision images to make this system more practical.
Keywords：virtual reality，ventricular plastic surgery，incision，excision
Abstract:A surgical plan of lett ventricular muscle is only determined by muscle palpation which identify the diseased and thin regions due to the cardiac infarction and dilate cardiomyopathy in the operative room．In order to make more opportmities of cardiac palpation，cardiac surgeons strongly desire a training system for the cardiac muscle palpation.The training system we have developed is composed of a virtual heart model based on the medical image data of human heart，the cardiac muscular characteristics of animals，the haptic multi－finger manipulator．Our experiments show that the trainee can feel the dymamic elasticity of the virtual heart in his /her fingertips．Improvement of the human interface and adjustments of mechanical parameters based on the cardiac surgeon's evaluation will make this system more practical．
Keywords：Virtual heart，Real－time processing，and Surgical simulation
Abstract：Force feed back is one of the most essential functions in surgical
training．To avoid applying unecessary and injurious force to the tissue，trainees
and trainers must know how much force the trainees are exerting as they
handle surgical tools．Our goal is to develop an endoscopic sinus surgery（ESS）training
system with force and／or position sensors for surgical skill evaluation．This
paper presents a new method with Mixed Reality（MR）technology in our training
system:the 3D image of surgical force and torque vectors，or the position
of a surgical tool is overlaid on an endoscopic image．
Keywords：surgical training，endoscopic sinus surgery，Mixed Reality