Guidance Project

Noby hata Jayender Jagadeesan Junichi Tokuda
Nobuhiko Hata, PhD
Core Lead
Jayender Jagadeesan, PhD
Project Lead
Junichi Tokuda, PhD
Project Lead

The long-term goal of Guidance Core is to provide novel guidance methods to improve the outcome of therapies of dynamically deforming and moving organs. This involves developing unique tissue-embedded wireless electromagnetic sensors (EM) and MR-tracked catheters to verify their feasibility and impact on the clinical procedures performed at the Advanced Multimodality Image Guided Operating Room (AMIGO). Projects within this Core are:

Integrated navigation system to accurately localize the tumor and guide the surgical instrument to the optimal resection margin in presence of significant tissue deformation.  We are developing hardware for the integrated navigation system to enable real-time tumor and instrument tracking; a tumor deformation model to estimate the tumor position and optimal resection margin; software for the integrated navigation system to visualize the tumor and surgical instrument. We continue to validate the design and performance of the integrated navigation system in ex-vivo phantoms and in human clinical trials. (Contact: Jayender Jagadeesan)

Verify the ability of active MRI-tracked metallic interventional devices to improve interventions through improved positional accuracy and improved therapy delivery. We are developing a miniature MRI tracking coil array embedded in flexible and rigid metallic stylets and catheters and improving dedicated MR-tracking pulse sequences to locate the devices so as to rapidly and accurately guide insertion of these devices in soft tissue and to monitor the non-rigid deformation of the target tissues. This is expected to enable clinicians to correct the access path based on these data. In addition, motional data provided by the devices is expected to aid in motion-compensated oxygenation imaging for radiation-dose augmentation to hypoxic tumor segments that resist radiation therapy. (Contact: Junichi Tokuda)

Software and Documentation

Links

Full Publication List

Peer-reviewed publications on our research can be found in the NIH/NLM database of biomedical literature by clicking here.

In addition, abstracts presented at national and international meetings are available online here.

Select Recent Publications

Schmidt EJ, Watkins RD, Zviman MM, Guttman MA, Wang W, Halperin HA. A Magnetic Resonance Imaging–Conditional External Cardiac De brillator for Resuscitation within the Magnetic Resonance Imaging Scanner Bore. Circ Cardiovasc Imaging. 2016;9 :e005091.Abstract

Subjects undergoing cardiac arrest within a magnetic resonance imaging (MRI) scanner are currently removed from the bore and then from the MRI suite, before the delivery of cardiopulmonary resuscitation and de brillation, potentially increasing the risk of mortality. This precludes many higher-risk (acute ischemic and acute stroke) patients from undergoing MRI and MRI-guided intervention. An MRI-conditional cardiac de brillator should enable scanning with de brillation pads attached and the generator ON, enabling application of de brillation within the seconds of MRI after a cardiac event. An MRI-conditional external de brillator may improve patient acceptance for MRI procedures. Methods and Results—A commercial external de brillator was rendered 1.5 Tesla MRI-conditional by the addition of novel radiofrequency lters between the generator and commercial disposable surface pads. The radiofrequency lters reduced emission into the MRI scanner and prevented cable/surface pad heating during imaging, while preserving all the de brillator monitoring and delivery functions. Human volunteers were imaged using high speci c absorption rate sequences to validate MRI image quality and lack of heating. Swine were electrically brillated (n=4) and thereafter de brillated both outside and inside the MRI bore. MRI image quality was reduced by 0.8 or 1.6 dB, with the generator in monitoring mode and operating on battery or AC power, respectively. Commercial surface pads did not create artifacts deeper than 6 mm below the skin surface. Radiofrequency heating was within US Food and Drug Administration guidelines. De brillation was completely successful inside and outside the MRI bore. Conclusions—A prototype MRI-conditional de brillation system successfully de brillated in the MRI without degrading the image quality or increasing the time needed for de brillation. It can increase patient acceptance for MRI procedures.