@article {Sciubba2010, title = {Percutaneous computed tomography fluoroscopy-guided conformal ultrasonic ablation of vertebral tumors in a rabbit tumor model. Laboratory investigation.}, journal = {J Neurosurg Spine}, volume = {13}, number = {6}, year = {2010}, month = {Dec}, pages = {773{\textendash}779}, publisher = {Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland 21287, USA. dsciubb1@jhmi.edu}, abstract = {

Radiofrequency ablation (RFA) has proven to be effective for treatment of malignant and benign tumors in numerous anatomical sites outside the spine. The major challenge of using RFA for spinal tumors is difficulty protecting the spinal cord and nerves from damage. However, conforming ultrasound energy to match the exact anatomy of the tumor may provide successful ablation in such sensitive locations. In a rabbit model of vertebral body tumor, the authors have successfully ablated tumors using an acoustic ablator placed percutaneously via computed tomography fluoroscopic (CTF) guidance.Using CTF guidance, 12 adult male New Zealand White rabbits were injected with VX2 carcinoma cells in the lowest lumbar vertebral body. At 21 days, a bone biopsy needle was placed into the geographical center of the lesion, down which an acoustic ablator was inserted. Three multisensor thermocouple arrays were placed around the lesion to provide measurement of tissue temperature during ablation, at thermal doses ranging from 100 to 1,000,000 TEM (thermal equivalent minutes at 43{\textdegree}C), and tumor volumes were given a tumoricidal dose of acoustic energy. Animals were monitored for 24 hours and then sacrificed. Pathological specimens were obtained to determine the extent of tumor death and surrounding tissue damage. Measured temperature distributions were used to reconstruct volumetric doses of energy delivered to tumor tissue, and such data were correlated with pathological findings.All rabbits were successfully implanted with VX2 cells, leading to a grossly apparent spinal and paraspinal tissue mass. The CTF guidance provided accurate placement of the acoustic ablator in all tumors, as corroborated through gross and microscopic histology. Significant tumor death was noted in all specimens without collateral damage to nearby nerve tissue. Tissue destruction just beyond the margin of the tumor was noted in some but not all specimens. No neurological deficits occurred in response to ablation. Reconstruction of measured temperature data allowed accurate assessment of volumetric dose delivered to tissues.Using a rabbit intravertebral tumor model, the authors have successfully delivered tumoricidal doses of acoustic energy via a therapeutic ultrasound ablation probe placed percutaneously with CTF guidance. The authors have thus established the first technical and preclinical feasibility study of controlled ultrasound ablation of spinal tumors in vivo.

}, keywords = {Animals, Carcinoma, Catheter Ablation, Fluoroscopy, instrumentation/methods, Lumbar Vertebrae, Male, Neoplasm Transplantation, Rabbits, Spinal Neoplasms, therapy, Tomography, X-Ray Computed}, doi = {10.3171/2010.5.SPINE09266}, url = {http://dx.doi.org/10.3171/2010.5.SPINE09266}, author = {Daniel M Sciubba and E. Clif Burdette and Jennifer J Cheng and William A Pennant and Joseph C Noggle and Rory J Petteys and Christopher Alix and Chris J Diederich and Gabor Fichtinger and Ziya L Gokaslan and Kieran P Murphy} } @article {Fichtinger2008b, title = {Robotic assistance for ultrasound-guided prostate brachytherapy}, journal = {Medical Image Analysis}, volume = {12}, number = {5}, year = {2008}, month = {06/2008}, pages = {535}, publisher = {Queen{\textquoteright}s University; 25 Union Street;725 Goodwin Hall; Kingston; ON; Canada gabor@cs queensu ca}, abstract = {

We present a robotically assisted prostate brachytherapy system, test results in training phantoms, Phase-I clinical trials The system consists of a transrectal ultrasound (TRUS), a spatially co-registered robot,fully integrated with an FDA-approved commercial treatment planning system The salient feature of the system is a small parallel robot affixed to the mounting posts of the template The robot replaces the template interchangeably,using the same coordinate system Established clinical hardware,workflow, calibration remain intact In all phantom experiments,we recorded the first insertion attempt without adjustment All clinically relevant locations in the prostate were reached Non-parallel needle trajectories were achieved The pre-insertion transverse, rotational errors (measured with a Polaris optical tracker relative to the template{\textquoteright}s coordinate frame) were 0 25 mm (STD=0 17 mm), 0 75 degrees (STD=0 37 degrees) In phantoms,needle tip placement errors measured in TRUS were 1 04 mm (STD=0 50mm) A Phase-I clinical feasibility, safety trial has been successfully completed with the system We encountered needle tip positioning errors of a magnitude greater than 4mm in only 2 of 179 robotically guided needles,in contrast to manual template guidance where errors of this magnitude are much more common Further clinical trials are necessary to determine whether the apparent benefits of the robotic assistant will lead to improvements in clinical efficacy, outcomes

}, keywords = {Brachytherapy, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Humans, instrumentation, instrumentation/methods, Interventional, Male, Prostatic Neoplasms, Radiotherapy, radiotherapy/ultrasonography, Robotics, Ultrasonography}, doi = {10 1016/j media 2008 06 002}, url = {http://dx doi org/10 1016/j media 2008 06 002}, author = {Gabor Fichtinger and Jonathan Fiene and Christopher Kennedy and Gernot Kronreif and Iulian Iordachita and Danny Y Song and E. Clif Burdette and Peter Kazanzides} } @conference {Karim-Aghaloo2008, title = {Towards detecting surgical clips in 3D ultrasound for target localization in radiation therapy: a study on tissue phantoms}, booktitle = {International Conference of the IEEE Engineering in Medicine and Biology Society}, volume = {2008}, year = {2008}, pages = {5282{\textendash}5285}, publisher = {Department of Electrical, Computer Engineering, Queens University, Kingston, ON K7L3N6, Canada}, organization = {Department of Electrical, Computer Engineering, Queens University, Kingston, ON K7L3N6, Canada}, abstract = {

A study is performed to measure the visibility of small surgical clips in 3D ultrasound volumes of a phantom as the first step towards using such clips as fiducial markers in radiation therapy Visibility is calculated as the contrast to noise ratio of the echo from the clip to the background The appearance of a resonance tail is also calculated using a moment analysis Contrast is found to be high, mostly independent of material, size of the clip All clips are visible, but the length of the tail is found to be dependent on clip orientation to the ultrasound beam The consistent visibility of the clips suggests they are suitable as fiducial markers in ultrasound, the dependency of the resonance tail on orientation provides an opportunity to distinguish clips from other specular reflectors

}, keywords = {Computer-Assisted, Equipment Design, Equipment Failure Analysis, Humans, Image Enhancement, Imaging, instrumentation, instrumentation/methods, methods, Phantoms, Radiotherapy, Reproducibility of Results, Sensitivity, Specificity, Surgical Instruments, Three-Dimensional, Ultrasonography}, doi = {10 1109/IEMBS 2008 4650406}, url = {http://dx doi org/10 1109/IEMBS 2008 4650406}, author = {Zahra Karim-Aghaloo and Prasad Shrawane and Purang Abolmaesumi and Gabor Fichtinger and Robert Rohling} } @article {Rivaz2008a, title = {Ultrasound elastography: a dynamic programming approach}, journal = {IEEE transactions on medical imaging}, volume = {27}, number = {10}, year = {2008}, month = {Oct}, pages = {1373{\textendash}1377}, publisher = {Engineering Research Center for Computer Integrated Surgery, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA}, abstract = {

This paper introduces a 2-D strain imaging technique based on minimizing a cost function using dynamic programming (DP) The cost function incorporates similarity of echo amplitudes, displacement continuity Since tissue deformations are smooth, the incorporation of the smoothness into the cost function results in reduced decorrelation noise As a result, the method generates high-quality strain images of freehand palpation elastography with up to 10\% compression, showing that the method is more robust to signal decorrelation (caused by scatterer motion in high axial compression, nonaxial motions of the probe) in comparison to the standard correlation techniques The method operates in less than 1 s, is thus also potentially suitable for real time elastography

}, keywords = {Algorithms, Computer-Assisted, Elasticity Imaging Techniques, Humans, Image Enhancement, Image Interpretation, Imaging, instrumentation/methods, methods, Numerical Analysis, Phantoms, Sensitivity, Specificity}, doi = {10 1109/TMI 2008 917243}, url = {http://dx doi org/10 1109/TMI 2008 917243}, author = {Hassan Rivaz and Emad Boctor and Pezhman Foroughi and Richard Zellars and Gabor Fichtinger and Gregory D. Hager} } @article {Krieger2007a, title = {Design and preliminary accuracy studies of an MRI-guided transrectal prostate intervention system}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 2}, year = {2007}, pages = {59{\textendash}67}, publisher = {Department of Mechanical Engineering, Johns Hopkins University, Baltimore, USA}, abstract = {

This paper reports a novel system for magnetic resonance imaging (MRI) guided transrectal prostate interventions, such as needle biopsy, fiducial marker placement, and therapy delivery The system utilizes a hybrid tracking method, comprised of passive fiducial tracking for initial registration, subsequent incremental motion measurement along the degrees of freedom using fiber-optical encoders, mechanical scales Targeting accuracy of the system is evaluated in prostate phantom experiments Achieved targeting accuracy, procedure times were found to compare favorably with existing systems using passive, active tracking methods Moreover, the portable design of the system using only standard MRI image sequences, minimal custom scanner interfacing allows the system to be easily used on different MRI scanners

}, keywords = {Algorithms, Artificial Intelligence, Automated, Biopsy, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Humans, Image Enhancement, Image Interpretation, Imaging, instrumentation/methods, Interventional, Magnetic Resonance Imaging, Male, methods, Needle, pathology/surgery, Pattern Recognition, Pilot Projects, Prostatectomy, Prostatic Neoplasms, Rectum, Reproducibility of Results, Robotics, Sensitivity, Specificity, Three-Dimensional, User-Computer Interface}, author = {Axel Krieger and Csaba Csoma and Iulian Iordachita and Peter Guion and Anurag K. Singh and Gabor Fichtinger and Whitcomb, Louis L.} } @article {DiMaio2007, title = {Dynamic MRI scan plane control for passive tracking of instruments and devices}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 2}, year = {2007}, pages = {50{\textendash}58}, publisher = {Brigham, Women{\textquoteright}s Hospital, Harvard Medical School, Boston, MA, USA}, abstract = {

This paper describes a novel image-based method for tracking robotic mechanisms, interventional devices during Magnetic Resonance Image (MRI)-guided procedures It takes advantage of the multi-planar imaging capabilities of MRI to optimally image a set of localizing fiducials for passive motion tracking in the image coordinate frame The imaging system is servoed to adaptively position the scan plane based on automatic detection, localization of fiducial artifacts directly from the acquired image stream This closed-loop control system has been implemented using an open-source software framework, currently operates with GE MRI scanners Accuracy, performance were evaluated in experiments, the results of which are presented here

}, keywords = {Algorithms, Anatomy, Artificial Intelligence, Automated, Computer-Assisted, Cross-Sectional, Humans, Image Enhancement, Image Interpretation, Imaging, instrumentation/methods, Magnetic Resonance Imaging, methods, Pattern Recognition, Phantoms, Reproducibility of Results, Robotics, Sensitivity, Specificity, Surgery, Three-Dimensional, User-Computer Interface}, author = {Simon DiMaio and Eigil Samset and Gregory Fischer and Iulian Iordachita and Gabor Fichtinger and Ferenc Jolesz and Clare M Tempany} } @article {Jain2007, title = {Intra-operative 3D guidance in prostate brachytherapy using a non-isocentric C-arm}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 2}, year = {2007}, pages = {9{\textendash}17}, publisher = {Johns Hopkins University, USA}, abstract = {

Intra-operative guidance in Transrectal Ultrasound (TRUS) guided prostate brachytherapy requires localization of inserted radioactive seeds relative to the prostate Seeds were reconstructed using a typical C-arm, and exported to a commercial brachytherapy system for dosimetry analysis Technical obstacles for 3D reconstruction on a non-isocentric C-arm included pose-dependent C-arm calibration; distortion correction; pose estimation of C-arm images; seed reconstruction;, C-arm to TRUS registration In precision-machined hard phantoms with 40-100 seeds, we correctly reconstructed 99 8\% seeds with a mean 3D accuracy of 0 68 mm In soft tissue phantoms with 45-87 seeds, clinically realistic 15 degrees C-arm motion, we correctly reconstructed 100\% seeds with an accuracy of 1 3 mm The reconstructed 3D seed positions were then registered to the prostate segmented from TRUS In a Phase-1 clinical trial, so far on 4 patients with 66-84 seeds, we achieved intra-operative monitoring of seed distribution, dosimetry We optimized the 100\% prescribed iso-dose contour by inserting an average of 3 75 additional seeds, making intra-operative dosimetry possible on a typical C-arm, at negligible additional cost to the existing clinical installation

}, keywords = {Algorithms, Brachytherapy, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Humans, Imaging, instrumentation/methods, Interventional, Intraoperative Care, Male, methods, Prostatic Neoplasms, Prosthesis Implantation, Radiographic Image Enhancement, Radiographic Image Interpretation, Radiography, radiography/radiotherapy, Radiotherapy, Reproducibility of Results, Sensitivity, Specificity, Three-Dimensional, Tomography, X-Ray Computed}, author = {Ameet K. Jain and Anton Degeut and Iulian Iordachita and Gouthami Chintalapani and Jack Blevins and Le Yi and Elwood Armour and E. Clif Burdette and Danny Y Song and Gabor Fichtinger} } @article {Liu2007, title = {Prostate implant reconstruction with discrete tomography}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 1}, year = {2007}, pages = {734{\textendash}742}, publisher = {Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA}, abstract = {

We developed a discrete tomography method for prostate implant reconstructions using only a limited number of X-ray projection images A 3D voxel volume is reconstructed by back-projection, using distance maps generated from the projection images The true seed locations are extracted from the voxel volume while false positive seeds are eliminated using a novel optimal geometry coverage model The attractive feature of our method is that it does not require exact seed segmentation of the X-ray images, it yields near 100\% correct reconstruction from only six images with an average reconstruction accuracy of 0 86 mm (std = 0 46mm)

}, keywords = {Brachytherapy, Computer-Assisted, Humans, Imaging, instrumentation/methods, Male, methods, Prostatic Neoplasms, Prosthesis Implantation, Radiographic Image Enhancement, Radiographic Image Interpretation, radiography/radiotherapy, Three-Dimensional}, author = {Xiaofeng Liu and Ameet K. Jain and Gabor Fichtinger} } @article {Krupa2007, title = {Real-time tissue tracking with B-mode ultrasound using speckle and visual servoing}, journal = {Tenth International Conference on Medical Image Computing and Computer-Assisted Intervention (MICCAI)}, volume = {10}, number = {Pt 2}, year = {2007}, pages = {1{\textendash}8}, publisher = {IRISA - INRIA Rennes, France alexandre krupa@irisa fr}, abstract = {

We present a method for real-time tracking of moving soft tissue with B-mode ultrasound (US) The method makes use of the speckle information contained in the US images to estimate the in-plane, out-of-plane motion of a fixed target relative to the ultrasound scan plane The motion information is then used as closed-loop feedback to a robot which corrects for the target motion The concept is demonstrated for translation motions in an experimental setup consisting of an ultrasound speckle phantom, a robot for simulating tissue motion, and a robot that performs motion stabilization from US images This concept shows promise for US-guided procedures that require real-time motion tracking, compensation

}, keywords = {Algorithms, Artificial Intelligence, Computer Systems, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Image Enhancement, Image Interpretation, Imaging, instrumentation/methods, Interventional, methods, Pilot Projects, Reproducibility of Results, Robotics, Sensitivity, Specificity, Surgery, Three-Dimensional, Ultrasonography, User-Computer Interface}, author = {Alexandre Krupa and Gabor Fichtinger and Gregory D. Hager} } @article {DiMaio2007a, title = {Robot-assisted needle placement in open MRI: system architecture, integration and validation}, journal = {Journal of Computer Aided Surgery}, volume = {12}, number = {1}, year = {2007}, month = {Jan}, pages = {15{\textendash}24}, publisher = {Brigham, Women{\textquoteright}s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA simond@bwh harvard edu}, abstract = {

In prostate cancer treatment, there is a move toward targeted interventions for biopsy, therapy, which has precipitated the need for precise image-guided methods for needle placement This paper describes an integrated system for planning, performing percutaneous procedures with robotic assistance under MRI guidance A graphical planning interface allows the physician to specify the set of desired needle trajectories, based on anatomical structures, lesions observed in the patient{\textquoteright}s registered pre-operative, pre-procedural MR images, immediately prior to the intervention in an open-bore MRI scanner All image-space coordinates are automatically computed, and are used to position a needle guide by means of an MRI-compatible robotic manipulator, thus avoiding the limitations of the traditional fixed needle template Automatic alignment of real-time intra-operative images aids visualization of the needle as it is manually inserted through the guide Results from in-scanner phantom experiments are provided

}, keywords = {Biopsy, diagnosis, Humans, instrumentation/methods, Magnetic Resonance Imaging, Male, Needle, Neuronavigation, Prostatic Neoplasms, Robotics}, doi = {10 1080/10929080601168254}, url = {http://dx doi org/10 1080/10929080601168254}, author = {Simon DiMaio and Steve Pieper and Kiyoyuki Chinzei and Nobuhiko Hata and Steven Haker and Daniel Kacher and Gabor Fichtinger and Clare M Tempany and Ron Kikinis} } @article {Fichtinger2007c, title = {Robotic assistance for ultrasound guided prostate brachytherapy}, journal = {Medical Image Computing and Computer-Assisted Intervention (MICCAI)}, volume = {4791}, year = {2007}, pages = {119{\textendash}127}, publisher = {The Johns Hopkins University, Baltimore, Maryland, USA gabor@cs jhu edu}, abstract = {

We present a robotically assisted prostate brachytherapy system, test results in training phantoms The system consists of a transrectal ultrasound (TRUS), a spatially co-registered robot integrated with an FDA-approved commercial treatment planning system The salient feature of the system is a small parallel robot affixed to the mounting posts of the template The robot replaces the template interchangeably, uses the same coordinate system Established clinical hardware, workflow, calibration are left intact In these experiments, we recorded the first insertion attempt without adjustment All clinically relevant locations were reached Non-parallel needle trajectories were achieved The pre-insertion transverse, rotational errors (measured with Polaris optical tracker relative to the template{\textquoteright}s coordinate frame) were 0 25mm (STD = 0 17mm), 0 75 degrees (STD = 0 37 degrees) The needle tip placement errors measured in TRUS were 1 04mm (STD = 0 50mm) The system is in Phase-I clinical feasibility, safety trials, under Institutional Review Board approval

}, keywords = {Brachytherapy, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Humans, instrumentation/methods, Interventional, Male, Prostatic Neoplasms, Radiotherapy, Radiotherapy Planning, radiotherapy/ultrasonography, Robotics, Ultrasonography}, author = {Gabor Fichtinger and Jonathan Fiene and Christopher Kennedy and Gernot Kronreif and Iulian Iordachita and Danny Y Song and E. Clif Burdette and Peter Kazanzides} } @article {Fischer2007b, title = {Robotic assistant for transperineal prostate interventions in 3T closed MRI}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 1}, year = {2007}, pages = {425{\textendash}433}, publisher = {Center for Computer Integrated Surgery, Johns Hopkins University, USA gfischer@jhu edu}, abstract = {

Numerous studies have demonstrated the efficacy of image-guided needle-based therapy, biopsy in the management of prostate cancer The accuracy of traditional prostate interventions performed using transrectal ultrasound (TRUS) is limited by image fidelity, needle template guides, needle deflection, tissue deformation Magnetic Resonance Imaging (MRI) is an ideal modality for guiding, monitoring such interventions due to its excellent visualization of the prostate, its sub-structure, surrounding tissues We have designed a comprehensive robotic assistant system that allows prostate biopsy, brachytherapy procedures to be performed entirely inside a 3T closed MRI scanner We present a detailed design of the robotic manipulator, an evaluation of its usability, MR compatibility

}, keywords = {anatomy /\&/ histology/surgery, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Image Interpretation, instrumentation/methods, Interventional, Magnetic Resonance Imaging, Perineum, Prostatectomy, Robotics, Surgery}, author = {Gregory Fischer and Simon DiMaio and Iulian Iordachita and Gabor Fichtinger} } @article {Labat2007, title = {Toward optimal matching for 3D reconstruction of brachytherapy seeds}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {10}, number = {Pt 2}, year = {2007}, pages = {701{\textendash}709}, publisher = {Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA}, abstract = {

X-ray C-arm fluoroscopy is a natural choice for intra-operative seed localization in prostate brachytherapy Resolving the correspondence of seeds in the projection images can be modeled as an assignment problem that is NP-hard Our approach rests on the practical observation that the optimal solution has almost zero cost if the pose of the C-arm is known accurately This allowed us to to derive an equivalent problem of reduced dimensionality that, with linear programming, can be solved efficiently in polynomial time Additionally, our method demonstrates significantly increased robustness to C-arm pose errors when compared to the prior art Because under actual clinical circumstances it is exceedingly difficult to track the C-arm, easing on this constraint has additional practical utility

}, keywords = {Algorithms, Artificial Intelligence, Automated, Brachytherapy, Computer-Assisted, Image Enhancement, Image Interpretation, Imaging, instrumentation/methods, methods, Pattern Recognition, Phantoms, Prosthesis Implantation, Radiotherapy, Reproducibility of Results, Sensitivity, Specificity, Three-Dimensional, Tomography, X-Ray Computed}, author = {Christian Labat and Ameet K. Jain and Gabor Fichtinger and Jerry L. Prince} } @article {Jain2006a, title = {C-arm tracking and reconstruction without an external tracker}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {9}, number = {Pt 1}, year = {2006}, pages = {494{\textendash}502}, publisher = {Department of Computer Science, Johns Hopkins University, USA}, abstract = {

For quantitative C-arm fluoroscopy, we have developed a unified mathematical framework to tackle the issues of intra-operative calibration, pose estimation, correspondence, reconstruction, without the use of optical/electromagnetic trackers or precision-made fiducial fixtures Our method uses randomly distributed unknown points in the imaging volume, either naturally present or induced by randomly sticking beads or other simple markers in the image pace After these points are segmented, a high dimensional non-linear optimization computes all unknown parameters for calibration, C-arm pose, correspondence, reconstruction Preliminary phantom experiments indicate an average C-arm tracking accuracy of 0 9 degrees, a 3D reconstruction error of 0 8 mm, with an 80 region of convergence for both the AP, lateral axes The method appears to be sufficiently accurate for many clinical applications, and appealing since it works without any external instrumentation, does not interfere with the workspace

}, keywords = {Algorithms, Calibration, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Fluoroscopy, Imaging, instrumentation/methods, methods, Radiographic Image Enhancement, Radiographic Image Interpretation, Reproducibility of Results, Sensitivity, Specificity, Three-Dimensional}, author = {Ameet K. Jain and Gabor Fichtinger} } @article {Kazanzides2006, title = {Design, validation of an image-guided robot for small animal research}, journal = {Medical image computing and computer-assisted intervention (MICCAI)}, volume = {9}, number = {Pt 1}, year = {2006}, pages = {50{\textendash}57}, publisher = {Department of Computer Science, Johns Hopkins University, USA pkaz@jhu edu}, abstract = {

We developed an image-guided robot system to achieve highly accurate placement of thin needles, probes into in-vivo rodent tumor tissue in a predefined pattern that is specified on a preoperative image This system can be used for many experimental procedures where the goal is to correlate a set of physical measurements with a corresponding set of image intensities or, more generally, to perform a physical action at a set of anatomic points identified on a preoperative image This paper focuses on the design, validation of the robot system, where the first application is to insert oxygen measurement probes in a three-dimensional (3D) grid pattern defined with respect to a PET scan of a tumor The design is compatible with CT, MRI, which we plan to use to identify targets for biopsy, for the injection of adenoviral sequences for gene therapy The validation is performed using a phantom, includes a new method for estimating the Fiducial Localization Error (FLE) based on the measured Fiducial Distance Error (FDE)

}, keywords = {Animals, Biopsy, Computer-Assisted, Equipment Design, Equipment Failure Analysis, Imaging, Injections, instrumentation/methods, instrumentation/methods/veterinary, Needle, Phantoms, Positron-Emission Tomography, Research, Robotics, Surgery}, author = {Peter Kazanzides and Jenghwa Chang and Iulian Iordachita and Jack Li and Clifton Ling and Gabor Fichtinger} } @article {Susil2006, title = {Transrectal prostate biopsy and fiducial marker placement in a standard 1 5T magnetic resonance imaging scanner}, journal = {The Journal of Urology}, volume = {175}, number = {1}, year = {2006}, month = {Jan}, pages = {113{\textendash}120}, publisher = {Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA}, abstract = {

PURPOSE: We investigated the accuracy, feasibility of a system that provides transrectal needle access to the prostate concurrent with 1 5 Tesla MRI which previously has not been possible MATERIALS AND METHODS: In 5 patients with previously diagnosed prostate cancer, MRI guided intraprostatic placement of gold fiducial markers (4 procedures),/or prostate biopsy (3 procedures) was performed using local anesthesia RESULTS: Mean procedure duration was 76 minutes, all patients tolerated the intervention well Procedure related adverse events included self-limited hematuria, hematochezia following 3 of 8 procedures (all resolved in less than 1 week) Mean needle placement accuracy was 1 9 mm for the fiducial marker placement studies, 1 8 mm for the biopsy procedures Mean fiducial marker placement accuracy was 4 8 mm, the mean fiducial marker placement accuracy transverse to the needle direction was 2 6 mm All patients who underwent the procedure were able to complete their course of radiotherapy without delay or complication CONCLUSIONS: While studies of clinical usefulness are warranted, transrectal 1 5 T MRI guided prostate biopsy, fiducial marker placement is feasible using this system, providing new opportunities for image guided diagnostic, therapeutic prostate interventions

}, keywords = {Biopsy, Equipment Design, Feasibility Studies, Humans, instrumentation, instrumentation/methods, Magnetic Resonance Imaging, Male, Needle, pathology, Prostate, Prostatic Neoplasms}, doi = {10 1016/S0022-5347(05)00065-0}, url = {http://dx doi org/10 1016/S0022-5347(05)00065-0}, author = {Robert Susil and Cynthia Menard and Axel Krieger and Jonathan Coleman and Kevin Camphausen and Peter Choyke and Gabor Fichtinger and Whitcomb, Louis L. and Norman Coleman and Ergin Atalar} } @article {Krieger2005a, title = {Design of a novel MRI compatible manipulator for image guided prostate interventions}, journal = {IEEE Transactions on Biomedical Engineering}, volume = {52}, number = {2}, year = {2005}, month = {Feb}, pages = {306{\textendash}313}, abstract = {

This paper reports a novel remotely actuated manipulator for access to prostate tissue under magnetic resonance imaging guidance (APT-MRI) device, designed for use in a standard high-field MRI scanner The device provides three-dimensional MRI guided needle placement with millimeter accuracy under physician control Procedures enabled by this device include MRI guided needle biopsy, fiducial marker placements, and therapy delivery Its compact size allows for use in both standard cylindrical, open configuration MRI scanners Preliminary in vivo canine experiments, first clinical trials are reported

}, keywords = {Animals, Biopsy, Computer-Assisted, Dogs, Equipment Design, Equipment Failure Analysis, Feasibility Studies, Imaging, instrumentation/methods, Magnetic Resonance Imaging, Male, Micromanipulation, Needle, pathology/surgery, Prostate, Reproducibility of Results, Robotics, Sensitivity, Specificity, Surgery, Three-Dimensional}, doi = {10 1109/TBME 2004 840497}, url = {http://dx doi org/10 1109/TBME 2004 840497}, author = {Axel Krieger and Robert Susil and Cynthia Menard and Jonathan Coleman and Gabor Fichtinger and Ergin Atalar and Whitcomb, Louis L.} } @article {Jain2005a, title = {FTRAC}, journal = {Journal of Medical Physics}, volume = {32}, number = {10}, year = {2005}, month = {Oct}, pages = {3185{\textendash}3198}, abstract = {

C-arm fluoroscopy is ubiquitous in contemporary surgery, but it lacks the ability to accurately reconstruct three-dimensional (3D) information A major obstacle in fluoroscopic reconstruction is discerning the pose of the x-ray image, in 3D space Optical/magnetic trackers tend to be prohibitively expensive, intrusive, cumbersome in many applications We present single-image-based fluoroscope tracking (FTRAC) with the use of an external radiographic fiducial consisting of a mathematically optimized set of ellipses, lines, and points This is an improvement over contemporary fiducials, which use only points The fiducial encodes six degrees of freedom in a single image by creating a unique view from any direction A nonlinear optimizer can rapidly compute the pose of the fiducial using this image The current embodiment has salient attributes: small dimensions (3 x 3 x 5 cm); need not be close to the anatomy of interest;, accurately segmentable We tested the fiducial, the pose recovery method on synthetic data, also experimentally on a precisely machined mechanical phantom Pose recovery in phantom experiments had an accuracy of 0 56 mm in translation, 0 33 degrees in orientation Object reconstruction had a mean error of 0 53 mm with 0 16 mm STD The method offers accuracies similar to commercial tracking systems, and appears to be sufficiently robust for intraoperative quantitative C-arm fluoroscopy Simulation experiments indicate that the size can be further reduced to 1 x 1 X 2 cm, with only a marginal drop in accuracy

}, keywords = {Algorithms, Computer-Assisted, Fluoroscopy, Imaging, Information Storage, instrumentation/methods, methods, Phantoms, Radiographic Image Enhancement, Radiographic Image Interpretation, Reproducibility of Results, Retrieval, Sensitivity, Specificity, Three-Dimensional}, author = {Ameet K. Jain and Tabish Mustufa and Yu Zhou and E. Clif Burdette and Gregory Chirikjian and Gabor Fichtinger} } @article {Cleary2005, title = {Precision placement of instruments for minimally invasive procedures using a "needle driver" robot}, journal = {international journal of medical robotics computer assisted surgery MRCAS}, volume = {1}, number = {2}, year = {2005}, month = {Jan}, pages = {40{\textendash}47}, abstract = {

Medical practice continues to move toward less invasive procedures Many of these procedures require the precision placement of a needle in the anatomy Over the past several years, our research team has been investigating the use of a robotic needle driver to assist the physician in this task This paper summarizes our work in this area The robotic system is briefly described, followed by a description of a clinical trial in spinal nerve blockade The robot was used under joystick control to place a 22 gauge needle in the spines of 10 patients using fluoroscopic imaging The results were equivalent to the current manual procedure We next describe our follow-up clinical application in lung biopsy for lung cancer screening under CT fluoroscopy The system concept is discussed, the results of a phantom study are presented A start-up company named ImageGuide has recently been formed to commercialize the robot Their revised robot design is presented, along with plans to install a ceiling-mounted version of the robot in the CT fluoroscopy suite at Georgetown University

}, keywords = {Biopsy, Cadaver, Equipment Design, Fluoroscopy, Humans, Imaging, instrumentation, instrumentation/methods, Lung, Lung Neoplasms, methods, Minimally Invasive, Needles, Nerve Block, pathology, pathology/radiography, Phantoms, Randomized Controlled Trials as Topic, Robotics, Spinal Nerves, Surgical Procedures, Tomography, X-Ray Computed}, doi = {10 1002/rcs 40}, url = {http://dx doi org/10 1002/rcs 40}, author = {Kevin Cleary and Vance Watson and David Lindisch and Russell H. Taylor and Gabor Fichtinger and Sheng Xu and Charles White and John Donlon and Michael Taylor and Alexandru Patriciu and Dumitru Mazilu and Dan Stoianovici} } @article {Masamune2001, title = {System for robotically assisted percutaneous procedures with computed tomography guidance}, journal = {Journal of Computer Aided Surgery}, volume = {6}, number = {6}, year = {2001}, pages = {370{\textendash}383}, abstract = {

We present the prototype of an image-guided robotic system for accurate, consistent placement of percutaneous needles in soft-tissue targets under CT guidance inside the gantry of a CT scanner The couch-mounted system consists of a seven-degrees-of-freedom passive mounting arm, a remote center-of-motion robot, and a motorized needle-insertion device Single-image-based coregistration of the robot, image space is achieved by stereotactic localization using a miniature version of the BRW head frame built into the radiolucent needle driver The surgeon plans, controls the intervention in the scanner room on a desktop computer that receives DICOM images from the scanner The system does not need calibration, employs pure image-based registration, and does not utilize any vendor-specific hardware or software features In the open air, where there is no needle-tissue interaction, we systematically achieved an accuracy better than 1 mm in hitting targets at 5-8 cm from the fulcrum point In the phantom, the orientation accuracy was 0 6 degrees, and the distance between the needle tip, the target was 1 04 mm Experiments indicated that this robotic system is suitable for a variety of percutaneous clinical applications

}, keywords = {Biopsy, Computer-Assisted, Humans, Image Processing, Imaging, instrumentation, instrumentation/methods, Needle, Phantoms, Robotics, Surgery, Tomography, User-Computer Interface, X-Ray Computed}, doi = {10 1002/igs 10024}, url = {http://dx doi org/10 1002/igs 10024}, author = {Ken Masamune and Gabor Fichtinger and Alexandru Patriciu and Robert Susil and Russell H. Taylor and Louis Kavoussi and James Anderson and Ichiro Sakuma and Takeyoshi Dohi and Dan Stoianovici} }