CT COLOGRAPHY--VALIDATION AND VIRTUAL PREPARATION

Project: Research project

Project Details

Description

Computerized tomographic colography (CTC), a revolutionary new tool,
employs virtual reality technology to produce two- and three-dimensional
images that permit a thorough and minimally invasive evaluation of the
entire colorectal structure. This nascent imaging tool holds promise
in screening colorectal neoplasia as its sensitivity, specificity,
safety, cost-effectiveness, and patient acceptability, theoretically,
may approach the ideal. Given the societal importance of colorectal
cancer control and the limitations of currently used screening
approaches, there exists a strong rationale to aggressively investigate
CTC for a potential screening application. Our laboratory has completed
extensive preliminary work on this technology, and has published nearly
all peer reviewed clinical studies to date. It is our objective to
clinically validate CTC for the detection of colorectal neoplasia. The
proposal addresses aspects of central importance to the chemical
application of CTC in three inter-related but independent parts that
will be conducted in parallel. In Part I, the CTC technique will be
optimized by evaluating the use of radiopaque contrast material added
to the colonic lavage preparation, as well as the usefulness of prone
and supine CT scanning to eliminate problems with retained fluid and
collapsed bowel segments. The combined clinical performance of an
optimized CTC will then be prospectively compared in blinded fashion to
that of the current screening modalities--fecal occult blood testing,
flexible sigmoidoscopy, barium enema, and colonoscopy. Patient
acceptance for each examination, as well as the cost-effectiveness
implications of observed performance outcomes, will be evaluated using
a predictive model. In Part II, methods will be studied to improve the
efficiency of image displays and interpretation. Methods to be studied
include a tissue characterization tool using textual analysis to
differentiate stool from polyps, and image display of entire segments
of the colon using 3D rendered views of the colon (virtual pathology).
In Part III, computerized discrimination and subtraction of stool will
be explored. Virtual bowel preparation as a patient-friendly
alternative to lavage cleansing will be investigated, in which contrast-
tagged stool is electronically purged from the CTC image. The study is
fiscally responsible and capitalizes on the abundant clinical and
laboratory resources within the Mayo Medical Center. Data generated
should provide for a balanced appraisal of the value and practically of
this potentially powerful new screening tool.
StatusNot started