MR-Guided Needle Interventions & Beyond

Wednesday 14 May 2014

Benjamin P Grabow¹, Jonathan A Oler², Marissa Riedel², Eva M Fekete², Rothem Kovner², Ethan K Brodsky^1,3, Andrew S Fox⁴, Patrick H Roseboom², Marina E Emborg¹, Ned H Kalin², and Walter F Block^1,3
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.

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 Pertschuk^4
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.

Daisuke Kokuryo¹, Peng Mi^2,3, 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 Kataoka^2,6
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.

Sherif G. Nour^1,2, Tracy E. Powell^1,2, Justin A. Saunders^3,4, Brent Hayek^3,4, Hee Joon Kim^3,4, and Ted H. Wojno^3,4
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.

Alastair Martin¹, Jill Ostrem², Leslie Markun², Paul Larson³, Monica Volz³, and Philip Starr^3
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

Julien Garnon¹, Elodie Breton², Gorislav Erceg², Georgia Tsoumakidou¹, Michel de Mathelin², and Afshin Gangi^1
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.

Wei Wang^1,2, 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. Schmidt^1
1Radiology, Brigham & Women’s Hospital, Harvard Medical School, Boston, MA, United States, ²Radiation Oncology, Brigham & Women’s 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 & Women’s 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.

Tobias Penzkofer^1,2, Kemal Tuncali¹, Fiona M Fennessy^1,3, Junichi Tokuda¹, Andriy Fedorov¹, Sang-Eun Song¹, Nobuhiko Hata¹, and Clare M Tempany^1
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.

Di Xu^1,2, Steven M Shea^1,3, Wesley D Gilson¹, and Sunil G Patil^1
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.

Matthew Toews¹, Chang-Sheng Mei¹, Renxin Chu¹, W. Scott Hoge¹, Lawrence P Panych¹, and Bruno Madore^1
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.