For Immediate Release
Contact:
mktgcomm@tams.com
PRESS RELEASE FROM JOHNS HOPKINS: MOST ADVANCED CT SCANNER IMPROVES IMAGING OF HEART,
AVOIDS NEED FOR SURGICAL INSPECTION
Newly installed 64-CT scanner makes diagnosis faster and easier to perform
Johns Hopkins Medicine has installed the latest computed tomography (CT) imaging
software and machinery, also known as a 64-slice computerized axial tomography (CAT)
scanner. The newly upgraded device produces precise diagnostic pictures within
five to 10 seconds for patients experiencing symptoms associated with heart attack.
In use at Hopkins since Feb. 21, the scanner is expected to replace many diagnostic
angiograms, the current gold standard for diagnostic coronary imaging.
The upgraded Hopkins scanner is one of two identical systems currently operating
in the United States, the other installed in Boston, Mass. Its use will be
the subject of a continuing medical education seminar attended by more than 300
cardiologists on Saturday, March 5, immediately preceding the 2005 Annual Scientific
Session of the American College of Cardiology (ACC) in Orlando, Fla.
“This added technology will dramatically alter the way we currently treat patients
with suspected coronary disease and chest pain,” says cardiologist João Lima, M.D.,
associate professor of medicine and radiology at The Johns Hopkins University School
of Medicine and its Heart Institute.
“By immediately and very quickly checking for blocked arteries, we can sort out
who is and is not at high risk of having a heart attack, and eliminate the need
for unnecessary cardiac catheterization,” he said. “And we no longer need to wait
until a patient is stabilized before performing this critical diagnostic test.”
The new scanner installed at Hopkins is an Aquilon 64 CFX multislice CT scanner,
manufactured by Toshiba. Similar devices also are manufactured by Siemens and General
Electric. Features include production of images at twice the speed and in
greater detail than the 32-slice, and picture quality so good it decreases the need
for invasive, more risky procedures, called angiograms or cardiac catheterization,
to check for arterial blocks.
Cardiac catheterization requires threading a thin tube from the groin area to the
heart’s arteries, where a dye is released to produce contrast X-rays. The procedure
also checks the function of heart valves and muscle, takes between 30 minutes and
45 minutes to perform, and requires almost an hour for recovery. Potential
complications include infection, heart attack and stroke, but they are rare.
“This new generation of technology puts CT scanning among the first diagnostic tests
performed, whereas it has been mostly performed until now only when necessary and
if circumstances permitted,” says cardiologist Eduardo Marbán, M.D., Ph.D., professor
and chief of cardiology at Hopkins. Marbán is also director of the Hopkins
Institute of Molecular Cardiobiology and the Michel Mirowski Professor in Cardiology.
Indeed, Hopkins will be leading a multicenter clinical trial to compare the clinical
effectiveness of cardiac catheterization to 64-slice CT imaging as the new standard
for diagnosing cardiovascular disorders.
To produce a CT image, computer-driven machinery passes X-rays through the body,
producing digitized signals that are detected and reconstructed. Each X-ray
measurement lasts just a fraction of a second and represents a “slice” of an organ
or tissue. The greater the number of detectors – the new device has a total
of 64 – the better the resolution of the picture. A computer then uses these
slices to reconstruct highly detailed, 3-D images of the heart and surrounding arteries.
In some cases, a patient is injected with a contrast solution to increase the visual
detail.
Each machine costs between $1.5 million and $2 million. A single test costs
approximately $700.
Fellow cardiologist and Hopkins chief of medicine Myron L. Weisfeldt, M.D., a professor
and past president of the American Heart Association, notes that the time between
new generations of imaging technology has shrunk dramatically. “Within just the
last few years, CT scanning technology has made incredible strides as a diagnostic
tool,” he says. Weisfeldt is also the William Osler Professor of Medicine
at Hopkins. “As recently as 2003, the technical gold standard used to be 16-CT,
in which a procedure would require a 20- to 30-second breath hold in the time it
takes to perform the scan. This lengthy, more complicated test really restricted
use of CT to experimental purposes.”
Sample images are available for viewing (courtesy of Toshiba) at:
http://www.hopkinsmedicine.org/Press_releases/2005/03_02_05.html