Project 1: Quantitative Molecular Imaging
The development of medical imaging approaches capable of quantifying concentrations of cancer-specific molecular features in tissue is critical to 1) the march toward microscopic sensitivity in cancer diagnose, and 2) the success of new molecularly targeted cancer therapeutics. Conventional molecular imaging approaches simply equate the signal measured from the uptake of a cancer-targeted imaging agent at some arbitrary time after injection with the concentration of molecular targeted by the agent. However, many additional characteristics can affect the degree of imaging agent uptake in a tissue (e.g., blood flow, vascular permeability, and interstitial pressure), thereby obfuscating the presumed relationship between agent uptake and targeted molecule concentration. The goal of this project is to explore the use of a secondary “untargeted” imaging agent to account for non-specific uptake of a targeted imaging agent.
The uptake of an imaging agent targeted to a cancer-specific molecule (top image) can be referenced to the
uptake of an untargeted imaging agent (middle image) to quantify the concentration of the molecule (bottom image).
Project 2: Small Animal Fluorescence Tomography
The goal of this project is to explore the limits of fluorescence tomography (the mapping of fluorescent sources within biological tissue). Small animal fluorescence tomography has the potential to be a relatively low-cost, highly sensitive tool for investigate tumor growth and response to therapeutics on a molecular level in preclinical studies. This work is in collaboration with the Optics in Medicine group at Dartmouth College.
Gadolinium-enhanced magnetic resonance image of a mouse head with a tumor in the left cerebral hemisphere (a). Fluorescence tomography image of the same mouse after injecting an epidermal growth factor receptor (EGFR) targeted fluorescent imaging agent (b). EGFR is overexpressed in many tumors compared to healthy tissue.
Project 3: Fluorescence Guided Surgery
We are working in collaboration with Dr. Richard W. Byrne, M.D., in the Department of Neurosurgery at Rush University to advance fluorescence-imaging methods of highlighting cancerous tissue versus healthy tissue during brain tumor resection surgery. Specifically, we are developing tracer kinetic models to computationally produce increased imaging contrast in tissue with abnormal blood flow, vascularity, and/or molecular signatures that are consistent with cancer.
Surgical field during brain tumor surgery immediately after intravascular injection of fluorescein (a non-specific fluorescent agent: the uptake of which can be used to evaluated vascular characteristics of the tissue).