"Coronary CT angiography has generated great enthusiasm in recent years, due to its diagnostic accuracy in assessing patients with known or suspected coronary artery disease," said Andrew J. Einstein, M.D., Ph.D., assistant professor of clinical medicine in radiology and director of cardiac CT research at Columbia University Medical Center. "However, that enthusiasm has been tempered by concern about the potentially high radiation dose received by patients."
In CT, numerous x-ray beams and a set of x-ray detectors rotate around the patient, measuring the amount of radiation being absorbed in the body. At the same time, the exam table moves through the scanner allowing the x-ray beam to follow a helical or spiral path.
Many coronary CT angiography exams are conducted on 64-detector row CT scanners, which can image four centimeters at a time. The latest generation of CT technology, a 320-detector row volume CT scanner, can image 16 centimeters—or the entire length of the heart—in a single rotation and within a single heartbeat.
In his study, Dr. Einstein and a team of researchers compared the radiation exposure incurred during a coronary CT angiography procedure using a 64-detector row helical scanning and volume scanning, using a 320-detector row volume CT scanner. Phantoms simulating the male and female body were imaged using six different scan modes.
Using standard 64-detector row helical scanning as the benchmark, the effective radiation dose was reduced by 91 percent from 35.4 millisieverts (mSv) to 4.4 mSv using optimized 320-detector row volume scanning.
"By imaging the entire heart in one piece, volume scanning eliminates artifacts due to seams or gaps between image sections," said Dr. Einstein. "Moreover, the x-ray tube is left on for only a brief duration, as little as .35 seconds."
According to Dr. Einstein, state-of-the-art CT technology emphasizes optimal image resolution with the ability to lower radiation dose through a variety of features and scan modes that adjust and modulate the dose based on the specific needs of the individual patient.
"As CT technology advanced from 16- to 64-slice capabilities, the radiation dose went up significantly," he said. "Today, technology development is going in the opposite direction, reducing radiation exposure."
Dr. Einstein emphasized that practitioners must pay careful attention to using the appropriate scan mode to obtain diagnostic information with the least amount of radiation exposure to the patient.
"Radiation Dose from Single-Heartbeat Coronary CT Angiography Performed with a 320-Detector Row Volume Scanner." Collaborating with Dr. Einstein were Carl D. Elliston, M.A., Andrew E. Arai, M.D., Marcus Y. Chen, M.D., Richard Mather, Ph.D., Gregory D. N. Pearson, M.D., Ph.D., Robert L. DeLaPaz, M.D., Edward Nickoloff, D.Sc, Ajoy Dutta, M.S., and David J. Brenner, Ph.D., D.Sc.
Disclosure: Dr. Mather is an employee of Toshiba America Medical Systems. Dr. Mather provided recommendations but had no control over the data included in the manuscript.
Radiology is edited by Herbert Y. Kressel, M.D., Harvard Medical School, Boston, Mass., and owned and published by the Radiological Society of North America, Inc. (http://radiology.rsnajnls.org/)
RSNA is an association of more than 44,000 radiologists, radiation oncologists, medical physicists and related scientists committed to excellence in patient care through education and research. (RSNA.org)
For patient-friendly information on CT angiography, visit RadiologyInfo.org.
Millions through license revenues
27.04.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
27.04.2017 | Life Sciences
27.04.2017 | Physics and Astronomy
27.04.2017 | Earth Sciences