Joint Annual Meeting ISMRM-ESMRMB 2014 10-16 May 2014 Milan, Italy

MR-Guided Needle Interventions & Beyond

Wednesday 14 May 2014
Silver  16:00 - 18:00 Moderators: Sherif G. Nour, M.D., F.R.C.R., Ehud Schmidt, Ph.D.

16:00 0672.   Alteration of Molecular Neurochemistry: MRI-guided Delivery of Viral Vectors to the Primate Amygdala
Benjamin P Grabow1, Jonathan A Oler2, Marissa Riedel2, Eva M Fekete2, Rothem Kovner2, Ethan K Brodsky1,3, Andrew S Fox4, Patrick H Roseboom2, Marina E Emborg1, Ned H Kalin2, and Walter F Block1,3
1Medical Physics, University of Wisconsin, Madison, WI, United States, 2Psychiatry, University of Wisconsin, Madison, WI, United States, 3Biomedical Engineering, University of Wisconsin, Madison, WI, United States, 4University of Wisconsin, Madison, WI, United States

Progress in understanding the genetic, neurochemical, and molecular bases of some psychiatric illnesses has opened the possibility of using viral vectors to deliver novel therapeutics to relevant neural circuits. As the desired volumetric drug distributions are a factor of ten smaller than the drug distribution volumes used in previous trials of neuroprotective factors in degenerative brain diseases, the requirements for precise guidance and monitoring are significantly higher. We demonstrate methodology for targeting the central amygdalar nucleus, a structure critical for coordinating the behavioral components of fear and anxiety, in a longitudinal, non-human primate study designed to alter anxiety temperament.

16:12 0673.   Convection Enhanced Delivery of Toca 511 into Recurrent GBM Under Real-Time MR Guidance
Alastair Martin1, Manish Aghi2, Adrian Kells2, John Bringas2, Paul Larson2, Geoffrey Bates3, Peter Piferi3, Douglas Jolly4, Joan Robbins4, Derek Ostertag4, Carlos Ibanez4, Harry Gruber4, Krystof Bankiewicz2, and Daniel Pertschuk4
1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Neurological Surgery, UCSF, CA, United States, 3MRI Interventions, Irvine, CA, United States, 4Tocagen, San Diego, CA, United States

Intra-operative MR methods are employed to administer an investigational retroviral replicating vector (vocimagene amiretrorepvec; Toca 511) in a series of 7 patients with GBM. MR targeting is employed to insert a stepped infusion cannula to selected sites within the tumor. The vector is infused via convection enhanced delivery and real-time intra-operative MR monitoring of the infusion process is achieved by mixing the vector with an MR contrast agent. Good volumetric coverage of the tumors was achieved, with minimal extra-tumoral extension or reflux along the cannula tract evident.

16:24 0674.   Intracerebral drug delivery treatment using a regularly-structured biodegradable gel for slow-release of gadolinium-containing nano-micelles in a glioblastoma model
Daisuke Kokuryo1, Peng Mi2,3, Tomoka Kurita4, Teruyuki Yatabe4, Horacio Cabral2, Sayaka Shibata1, Yoshihiro Muragaki5, Hiroshi Iseki5, Takamasa Sakai2, Ung-il Chung2, Nobuhiro Nishiyama3, Tsuneo Saga1, Ichio Aoki1, and Kazunori Kataoka2,6
1Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Chiba, Japan, 2Graduate School of Engineering, The University of Tokyo, Tokyo, Japan, 3Chemical Resources Laboratory, Tokyo Institute of Technology, Kanagawa, Japan, 4R&D Headquarters, Terumo Corporation, Kanagawa, Japan, 5Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan, 6Graduate School of Medicine, The University of Tokyo, Tokyo, Japan

A strategy using for providing efficient intracerebral drug delivery treatment was developed and evaluated using a combination of regularly-structured biodegradable gel and Gd-containing micelles. The Gd-micelles are slowly released from the gel for several days in vitro. For an in vivo glioblastoma model, the micelles with the gel did not show any leakage to the ventricle and the micelles were slowly and continuously released from the gel for 2-3 days. We conclude that the proposed strategy has the potential to provide effective brain tumor treatment.

16:36 0675.   Intraorbital Vascular Malformations: Treatment with MRI-Guided Sclerotherapy
Sherif G. Nour1,2, Tracy E. Powell1,2, Justin A. Saunders3,4, Brent Hayek3,4, Hee Joon Kim3,4, and Ted H. Wojno3,4
1Radiology and Imaging Sciences, Emory University Hospital, Atlanta, GA, United States, 2Interventional MRI Program, Emory University Hospital, Atlanta, GA, United States, 3Ophthalmology, Emory University Hospital, Atlanta, GA, United States, 4School of Medicine, Emory University, Atlanta, GA, United States

Congenital intraorbital vascular malformations represent a challenging subset of vascular anomalies. The limited space of the orbital cavity results in significant symptomatology while complicating surgical interventions. Conventional fluoroscopically guided sclerotherapy of these malformations has been limited by the inability to identify critical intraorbital structures. We introduce a technique for accessing and treating these lesions under MRI guidance. Initial results indicate the feasibility, safety, and efficacy of MRI guided and monitored sclerotherapy of these intraorbital vascular malformations.

16:48 0676.   Interventional MR Guided DBS in Pediatric Dystonia: Technical and Clinical Outcomes
Alastair Martin1, Jill Ostrem2, Leslie Markun2, Paul Larson3, Monica Volz3, and Philip Starr3
1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Neurology, UCSF, San Francisco, CA, United States, 3Neurological Surgery, UCSF, San Francisco, CA, United States

MR guided implantation of deep brain stimulators is demonstrated in a series of pediatric dystonia patients. In contrast to conventional implantation methodologies, the MR guided approach does not require an awake, cooperative patient. Thus, it is much more suitable to pediatric applications. Bilateral DBS electrodes are implanted in six dystonia patients with a mean age of eleven years. Highly accurate targeting accuracy is achieved and clinical outcomes, as measured by a standardized dystonia rating scale, are comparable with the best reported results using traditional surgical implantation methods

17:00 0677.   Cryoablation of malignant liver tumors under MRI-guidance: retrospective study
Julien Garnon1, Elodie Breton2, Gorislav Erceg2, Georgia Tsoumakidou1, Michel de Mathelin2, and Afshin Gangi1
1Interventional Radiology Department, Strasbourg University Hospital, Strasbourg, France, 2ICube, Strasbourg University - CNRS, Strasbourg, France

Over a period of 2 years, MRI-guided cryoablations were performed in 10 patients presenting with complex cases of primary or secondary malignant liver tumors. Tumors (average diameter 2cm) were either not visible in CT/ultrasound, difficult to approach, or not treatable with radiofrequency ablation. Primary endpoint of this retrospective study was local recurrence in the ablated area. Over the follow-up period ranging from 8 to 44 months: local recurrence occurred in two patients; three patients died and one patient was lost to follow-up without evidence of local recurrence; other patients remained disease-free at the end of the study.

17:12 0678.   
Real-time active-tracking of metallic needles during MR-guided radiation therapy: from concept to the first human trial
Wei Wang1,2, Zion T. H. Tse3, Wolfgang Loew4, Charles L. Dumoulin4, Isaiah Norton5, Ravi T. Seethamraju6, Antonio L. Damato2, Tina Kapur1, Akila N. Viswanathan2, Robert A. Cormack2, and Ehud J. Schmidt1
1Radiology, Brigham & Womenís Hospital, Harvard Medical School, Boston, MA, United States, 2Radiation Oncology, Brigham & Womenís Hospital, Harvard Medical School, Boston, MA, United States, 3Engineering, University of Georgia, GA, United States, 4Radiology, Cincinnati Children's Hospital, OH, United States, 5Neurosurgery, Brigham & Womenís Hospital, Harvard Medical School, Boston, MA, United States, 6Siemens Healthcare, MA, United States

MRI is increasingly used for radiation treatment, due to improved visualization of the tumor and its surroundings. An active tracking application was developed enableing rapid and accurate real-time tracking of a metallic brachytherapy needle. The active-tracking device was built by adding printed-circuit microcoils to the needle. Because of its far-reaching lobe pattern, the coils can detect RF beyond the region where metal creates magnetic field disturbance. A tracking sequence with phase-field dithering removed B1 interference from neighboring metallic coils. The tracking system was tested in phantom and successfully applied to track needle placement in a endometrial cancer intervention.

17:24 0679.   Transperineal in-bore 3T MRI guided prostate biopsy in active surveillance patients: Higher prevalence of anteriorly located positive prostate cancer targets - permission withheld
Tobias Penzkofer1,2, Kemal Tuncali1, Fiona M Fennessy1,3, Junichi Tokuda1, Andriy Fedorov1, Sang-Eun Song1, Nobuhiko Hata1, and Clare M Tempany1
1Radiology, Brigham and Women's Hospital, Boston, MA, United States, 2Diagnostic and Interventional Radiology, RWTH Aachen University Hospital, Aachen, Germany, 3Radiology, Dana Farber Cancer Institute, Boston, MA, United States

Based on the known impact of prostate cancer localization within the gland on the success rate of guided prostate biopsy, we assessed the influence of target localization on positivity rate in a cohort of 20 patients in an active surveillance setting. Using in-bore transperineal MRI-guided prostate biopsy we found that anterior prostate gland targets have a significantly higher cancer yields than any other location in the gland when biopsied using this transperineal access, with a markedly lower number of cores compared to template mapping biopsy. This data could impact biopsy strategies and decision making in the active surveillance setting.

17:36 0680.   
B0 Drift and Respiratory Motion Correction by Dual-Echo Susceptibility Correction (DESC)
Di Xu1,2, Steven M Shea1,3, Wesley D Gilson1, and Sunil G Patil1
1Center for Applied Medical Imaging, Imaging and Computer Vision, Siemens Corporation, Corporate Technology, Baltimore, Maryland, United States,2Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, Baltimore, Maryland, United States, 3Department of Radiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, United States

A new B0 correction method known as Dual-Echo Susceptibility Correction (DESC) for Echo-planar (EP) based magnetic resonance imaging (MRI) is introduced. The proposed DESC method is comprised of 1) an acquisition of two EPI echoes; 2) modeling the susceptibility changes from B0 drift and respiratory motion using a smoothing polynomial function and 3) an iterative reconstruction framework to accurately estimate B0 corrected data. The DESC method is evaluated in an MR thermometry application as a proof of concept. It is shown that the DESC method reduces B0 drift and respiratory motion-related inaccuracies, while being computationally efficient.

17:48 0681.   Detecting rapid organ motion using a hybrid MR-ultrasound setup and Bayesian data processing
Matthew Toews1, Chang-Sheng Mei1, Renxin Chu1, W. Scott Hoge1, Lawrence P Panych1, and Bruno Madore1
1Department of Radiology, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, United States

Modeling and compensating for patient motion can be an important aspect of MR-guided therapeutic procedures, such as biopsies or ablations. Rapid and irregular patient motion, such as coughing or gasping, is particularly challenging as it may degrade MR images and confound registration algorithms. This work proposes an approach to detecting rapid motion from 1D ultrasound (US) measurements within a hybrid MR-US motion tracking system. A Bayesian algorithm handles the flow of hybrid data, and a metric based on the instantaneous organ velocity along the US beam is employed to detect periods of unusual motion activity such as coughing.