Clinical studies demonstrate effectiveness of Siemens 64-slice CT scans
in cardiac care
16 October 2005
Three studies of 64-slice computed tomography (CT) in cardiac care have
been published in peer-reviewed journals by Siemens' clinical collaborators
in Switzerland, USA and Germany.
these studies, results derived from 64-slice CT were compared to traditional
invasive catheter angiography and intravascular ultrasound (IVUS). The
authors of all the articles highlight the Somatom Sensation 64's excellent
image quality with an isotropic spatial resolution of below 0.4 mm in all
routine and cardiac scan modes, enabling a new level of clinical confidence.
Using z-Sharp technology and a rotation speed of 0.33 seconds, the system
supplies high quantitative and qualitative diagnostic accuracy for the
non-invasive assessment of coronary artery stenoses, coronary plaque
composition and plaque burden in a broad spectrum of patients.
A study conducted by Leschka et al. from the University Hospital, Zurich,
Switzerland (1) investigated the accuracy of the Somatom
Sensation 64 for assessing hemodynamically significant stenoses of coronary
arteries in a consecutive patient population. The Somatom Sensation 64's
high performance allowed the examination of these patients without the use
of any special medication to lower the patients' heart rate. All coronary
vessels were included for evaluation and all segments could be evaluated.
The authors conclude that the Somatom Sensation 64 provides a high
diagnostic accuracy in assessing coronary artery stenosis, compared to
conventional invasive angiography.
These results were confirmed by the group of Raff et al. from William
Beaumont Hospital, Royal Oak, Michigan (2), by comparing
the accuracy of the Somatom Sensation Cardiac 64 in detecting and accurately
measuring coronary lesions compared to conventional angiography including
Quantitative Coronary Analysis. The results indicate high quantitative and
qualitative diagnostic accuracy of 64-slice multislice CT in a broad
spectrum of patients, also including those patients who are obese and/or
have heavily calcified coronary arteries.
Another research team from Klinikum Grosshadern, University of Munich
(3), led by Leber et al., evaluated the accuracy of the
Somatom Sensation 64 to detect and differentiate different types of coronary
plaques, and to determine plaque burden compared to IVUS. The authors found
that the measurements of plaque and lumen area by CT correlated very well
with measurements performed with IVUS.
The Somatom Sensation 64 incorporates Siemens proprietary z-Sharp
Technology, which allows two focal points from the anode via precise
deflection of the electron beam within the X-ray tube, generating two
overlapping beams that pass the scan field. The double readout of the
detector produces 64 slice projections down to 0.3 mm slice distance without
increasing the radiation dose beyond a 16-slice CT. Furthermore, Siemens'
proprietary high-speed, ultra fast ceramic detector enables a virtually
simultaneous read-out of two projections for each detector element,
resulting in 64-slice acquisition. With z-Sharp Technology the system
delivers optimal image quality with a routine isotropic resolution of below
0.4 millimeters, firmly establishing a new benchmark for diagnostic
With the combination of Speed4D™ Technology and the world's fastest
gantry rotation speed of up to 0.33 seconds, the Somatom Sensation 64 also
offers the fastest scan speed, achieving a temporal resolution of up to 83
milliseconds, and thus facilitates scanning of patients even with higher
heart rates, virtually freezing the heart's motion. For the first time, this
CT performance allows for the evaluation of the most common causes of acute
chest pain with a single scan.
The Somatom Sensation 64 computed tomography (CT) system has more than
350 installations worldwide. Over 40% of these installations include the
Somatom Sensation Cardiac 64, which specialises in the diagnosis and
treatment of cardiovascular disease.
1. Sebastian Leschka*, Hatem Alkadhi*, André Plass+,
Lotus Desbiolles*, Juerg Gruenenfelder+, Borut Marincek*, and Simon
Wildermuth*; Accuracy of MSCT coronary angiography with 64-slice technology:
first experience. European Heart Journal, Advance Access, April 19, 2005.
*+University Hospital Zurich, Switzerland, *Department of Medical Radiology,
Institute of Diagnostic Radiology, +Clinic for Cardiovascular Surgery
2. Gilbert L. Raff*, Michael J. Gallagher*, William W.
O'Neill*, James A. Goldstein*; Diagnostic Accuracy of Noninvasive Coronary
Angiography Using 64-Slice Spiral Computed Tomography. Journal of the
American College of Cardiology, Vol. 46, 3, July 2005.
*William Beaumont Hospital, Royal Oak, MI., USA, Cardiology Division
3. Alexander W. Leber*, Andreas Knez*, Alexander Becker*,
Franz von Ziegler*, Konstantin Nikolaou+, Bernd Ohnesorge#, Maximilian
Reiser+, Gerhard Steinbeck*, Christoph R. Becker+, Peter Boekstegers*;
Accuracy of 64-slice CT to classify and quantify coronary plaque volumes. A
comparative study with intravascular ultrasound. Journal of the American
College of Cardiology, Vol. 46, 1, July 2005.
*+Klinikum Grosshadern, University of Munich, Munich, Germany, *Department
of Cardiology; +Institute for Diagnostic Radiology; #Siemens Medical
Solutions, Forchheim, Germany