events

LAMMP/BME Seminar Series

Thursday 05th of November 2009
12:00 PM
Beckman Laser Institute Library

Functional- and molecular- tomography of blushing brains and glowing mice

Joseph Culver, PhD
Mallinckrodt Institute of Radiology Department of Radiology Washington University School of Medicine

Our lab explores ways of leveraging non-invasive optical measurements for both functional- and molecular- biological imaging. For application in humans, optical neuroimaging has never lacked clinical potential, due to its ability to longitudinally and non-invasively monitor brain function. However, progress towards the bedside practice of methods to map brain function, such as functional near infrared spectroscopy (fNIRS), has been hindered by conceptual and technical limitations. One obstacle is that task-based neuroimaging, which is standard in cognitive neuroscience research, is generally ill-suited to clinical populations since they may be unable to perform any task. In this talk, we will demonstrate the feasibility of a task-less DOT approach to mapping brain function. The resting state approach analyzes spatio-temporal correlations in the data to develop maps of functional connectivity. Functional connectivity DOT (fc-DOT) methods provide a task-less approach to mapping brain function in populations that were previously difficult to research. These advances may permit new studies of early childhood development and of unconscious patients.
Within small animals, optical approaches can leverage a vast array of molecular imaging contrasts to provide high sensitivity, stable non-radioactive probes, and an wide variety of functional reporting strategies. For example optical methods can reveal cancer progression by imaging events such angiogenesis and metastases. While bioluminescence and fluorescence reflectance planar imagers provide quick assessments, quantitative localization is lacking due to strong depth dependence in sensitivity and poor resolution. We are developing a small animal fluorescence tomography (FT) platform to address these imaging challenges. Currently we are extending our FT platform into the time domain (~1ns) to improve a number of image quality metrics and further expand our biological reporting strategies. The current human studies, with intrinsic hemoglobin contrast, provide a pathway for eventual translation of these extrinsic molecular imaging approaches.