Massachusetts General Hospital
Development of a computer-controlled motion phantom
(Sheri Weinberg, Vo Van Toi, Steve Jiang)

We strongly feel there is need for a computer-controlled motor-driven motion phantom to simulate tumor motion. The phantom motion will follow precisely the measured tumor trajectory that is inputted into the computer. Such a phantom will be very useful for

1. studying the organ motion effect during the imaging and/or treatment delivering processes,
2. testing various motion mitigation techniques such as respiratory gating and motion compensation, and more importantly,
3. performing quality assurance for individual patients before treated with motion mitigation techniques. We have been working on this project with Dr. Vo Van Toi and Ms. Sheri Weinberg at Tufts University. A prototype has been developed, as shown in this picture. Currently, we are working on the system validation using a video-based approach.

MGH/MIT/HMS
Athinoula A. Martinos Center for Functional and Structural Biomedical Imaging
NMR Compatible Bioreactor for Tissue Engineering

Greg Altman, Ph.D., Department of Biomedical Engineering, Tufts University
Jerry Ackerman, Ph.D., NMR Center, Massachusetts General Hospital

There exists a tremendous need for advanced bioreactor systems that support the maintenance and development of various tissue types and functional states in vitro for use in tissue engineering. The goal of this proposal is to develop a bioreactor system that better approximates a variety of physiological environments while utilizing advances in non-destructive NMR imaging techniques to study the structure and function of engineered ligaments. The novelty of the system will lie in its real-time non-destructive assessment capabilities combined with advanced controllable close-loop mechanical, biochemical and fluidic control systems to mimic physiological conditions. A non-destructive method for assessing ligament tissue development would greatly enhance our ability to have an informed and directed strategy for identifying and perusing optimal culture conditions that support ligament development in vitro. We hypothesize that nuclear magnetic resonance (NMR) noninvasive near real-time imaging of bioreactor grown tissues is critical if more substantive scientific explorations of environment-cell-tissue responses are to be understood. The objective of the work will be to modify the existing ligament reactor vessel design to accommodate nondestructive NMR imaging of developing and cultured tissue engineered ligaments without sacrifice to the growth environment. The specific aims are as follows: Aim 1. Design and fabricate a NMR compatible reactor vessel for ligament tissue engineering. Aim 2. Test and validate reactor vessel design using previously established model system for ligaments. The final outcome of this work will be an instrumentation system by which researchers can better study the effects of environmental milieu on tissue development in vitro.