Boston Chapter of the IEEE Photonics Society

Abstract:  Molecular guidance of intervention could provide more specificity and higher likelihood of success in therapeutic outcome.  In this talk, methods and unique imaging systems being developed to advance molecular guidance towards metabolic and immunologic targeting are discussed.  The imaging is compared to the contrast possible with conventional structural x-ray and MRI based approaches.

One of the largest areas of R&D is for molecular probes that target cancer cell immune expression, however these often suffer of non-specific uptake issues from tumor enhanced permeability & retention. The use of ratiometric approaches to imaging receptor binding are demonstrated in lymph nodes and resected breast cancer tissue.  Structured light imaging can also help advance surgical guidance by providing a signal which is more specific to the sub-cellular organelle and stromal changes present in cancer.  

In radiation oncology, radiation dose imaging has been shown to be possible from gamma-ray and electron interactions emitting Cherenkov light, and this is a unique way to verify dosimetry in radiation therapy.  The major potential benefit of Cerenkov imaging is that it is a way to image beams in real time.  As such, it is feasible to image treatment beams in water tanks dynamically, and create composite visualizations of the treatment plans.  This imaging can be used to verify new treatment plans prior to application to patients, or to quickly verify new machines, or testing in situations where access is limited. In human imaging studies, two clinical trials have been completed to image surface emissions in real time during therapy.  In the first case, whole breast irradiation was followed for fractionated therapy in 12 patients.  

Finally, molecular imaging using the radiotherapy-induced Cerenkov as an internal tissue excitation system is shown, allowing high–resolution sensing of metabolites.  This is demonstrated in tissue phantoms as well as mouse studies, sensing molecular oxygen in lymph nodes in vivo. The extension of this to molecular guidance of radiation therapy seems feasible, or for using Cerenkov sensing as a diagnostic tool for cancer.

Biography:  Brian Pogue is Professor of Engineering, Physics & Astronomy, and Surgery at Dartmouth College in Hanover, NH, where he is director of MS and PhD Programs in Engineering.  He has a Ph.D. in Medical/Nuclear Physics from McMaster University, Canada, was a post-doctoral fellow at the Harvard Medical School.  At Dartmouth since 1996, he founded the Imaging and Interventional Technologies Center at Dartmouth, focusing on advance optical imaging technologies in cancer diagnosis & management. He has published over 300 peer-reviewed papers and 400 conference proceedings in imaging, tomography, surgery, medical oncology and radiotherapy.  His NCI funded research program helps maintain the Optics in Medicine laboratory at Dartmouth, housing over two dozen faculty, staff and students. He is currently an editorial board member for Physics in Medicine & Biology, Medical Physics, the Journal of Biomedical Optics, and Breast Cancer Research and was elected a Fellow of the Optical Society of America (OSA) and the American Institute of Medical and Biological Engineering (AIMBE).

Location:  MIT Lincoln Laboratory Forbes Road