The specific am of proposed project
is to modify an existing laboratory prototype instrument, designed
for research investigations, to render it suitable to perform clinical
studies for the purpose of demonstrating its commercial potential
for imaging important features related to the dynamics of the vascular
system. Current imaging technologies used to evaluate the vascular
system are limited to assessment of anatomic features or measurement
of flow in large, near surface vessels. In many cases, the critical
issue is vascular sufficiency and its corollary, vascular dynamics
(e.g., vasornotion, vascular reactivity). A direct measure of the
former would require deterrnination of tissue hemoglobin oxygen
saturation and tissue blood volume. While methods do exist to provide
indirect measure of these, none are capable of providing cross-sectional
images of large tissue structures (e.g., arms, legs, breast) revealing
the real-time dynamics of the vascular system. Recently, we have
demonstrated this capability in the human forearm using a previously
patented near infrared based imaging technology.
The commercial potential of this technology stems for the fact
that regardless of the specific etiology of a particular disease
process, alterations in the local tissue vascular supply, ranging
from neovascularization to blockage, can strongly influence disease
progression and response to drug therapy. In the case of neoplasms,
neovascularization is often disorganized invariably leading to hypoxic/
anoxic states and necrotic zones. The existence of such suites limits
the response to radiotherapy and availability of pharmacoactive
agents. While much basic understanding of the vascular system is
known, presently we lack detailed knowledge of local states especially
as they relate to issues of vascular sufficiency and its dynamic
properties. Noninvasive assessment of these could allow for improved
disease staging, and more optimal treatment planning. It could also
lead to new understandings of the influence of disease processes
on vascular dynamics, an area largely unexplored due to the lack
of suitable imaging technologies. |
