is a Professor of Radiology and Oncology and the Director of
Diagnostic Radiology and Body CT, Johns Hopkins Medical
Institutions, Baltimore, MD.
In March of 2005, I served as moderator of the fourth in a
series of Forums on the use of intravenous contrast in computed
tomographic angiography (CTA) applications. Proceedings of each of
the earlier Forums has been published as a special supplement to
, in print or online, or both.
CTA continues to evolve, especially as CT technology advances
from 4- to 16- to 32- to 40- to 64-detector rows. At the same time,
CTA is gaining wider acceptance with new and even more critical
clinical applications. It is no longer performed at select academic
healthcare institutions alone; rather, it is steadily becoming a
mainstream application at many institutions.
The goals of this supplement, which is based on the March 2005
CTA Forum, are to:
- Describe the current state of the art of CTA;
- Explore how changes in CTtechnology influence the use of
iodinated contrast media;
- Outline image acquisition and contrast administration
protocols for a variety of CTA applications;
- Provide guidance to healthcare centers just beginning to do
- Help experienced centers perform CTA more successfully.
Throughout the supplement, discussions on contrast
administration focus on the selection of contrast agent; contrast
volume, concentration, and rate of injection; the role of the
saline chaser; the timing of contrast delivery relative to data
acquisition; the role of image postprocessing; and the impact of
contrast agents on image quality.
Another important focus is the role and advantages of isosmolar
contrast medium, how to minimize or eliminate contrast-induced
nephropathy, and the identification of high-risk patients and
This supplement comprises an impressive array of review articles
by a distinguished panel of experts. In addition to my own overview
of 64-slice CT technology, Stanley Goldfarb, MD, from the
University of Pennsylvania School of Medicine (Philadelphia, PA),
pens an excellent review of contrast-induced nephropathy. Karen M.
Horton, MD, from Johns Hopkins Medical Institutions (Baltimore, MD)
addresses the controversies surrounding and appropriate role of
whole-body CT screening. Geoffrey Rubin, MD, of Stanford University
Medical Center (Palo Alto, CA), reviews the challenges and
techniques for lower-extremity CTA. Julia R. Fielding, MD, of the
University of North Carolina (Chapel Hill, NC), explores CTA of
cystic renal masses. Finally, Ella Kazerooni, MD, of the University
of Michigan Medical Center (Ann Arbor, MI), discusses present and
future applications of cardiac CTA.
I would like to thank GE Healthcare for sponsoring the CTA Forum
and for providing an educational grant in support of this
publication, Anderson Publishing for producing this special
supplement, and all of the Forum participants for preparing a
comprehensive overview of the use of intravenous contrast in
Contrast-induced nephropathy: Risk factors, pathophysiology, and