Techniques appear to lower radiation exposure from cardiac scans without impairing image quality
June 10, 2009An intervention that includes techniques to reduce the amount of radiation from cardiac computed tomography angiography (scanning used to diagnose coronary artery disease) was associated with decreasing patient exposure to radiation without significantly changing the quality of the images, according to a study in the June 10 issue of JAMA.
Coronary artery disease remains the most frequent cause of death and disability in the developed world and rates are increasing among developing nations. "As the population at risk has increased, national health care systems are under financial pressure to deliver cost-effective diagnosis and risk stratification of symptomatic patients suspected of having coronary ischemia. Noninvasive multislice cardiac computed tomography angiography (CCTA) has emerged since 2000 as a new diagnostic test with the potential to efficiently address this challenge," the authors write. Results from multiple studies suggest that CCTA may definitively exclude the diagnosis of coronary artery disease in a substantial proportion of appropriately selected patients, however radiation dose from this procedure is of concern.
Gilbert L. Raff, M.D., of William Beaumont Hospital, Royal Oak, Mich., and colleagues conducted a study to determine whether implementation of an intervention to improve the technique for scan acquisition would be associated with a reduction in the estimated radiation dose from CCTA and what would be the associated effects on image quality. The study included 4,995 patients undergoing CCTA for suspected coronary artery disease at 15 hospital imaging centers, which included small community hospitals and large academic centers; 4,862 patients (97.3 percent) had complete radiation data for analysis. The techniques to reduce radiation dose included minimized scan range, heart rate reduction, electrocardiographic-gated tube current modulation, and reduced tube voltage in suitable patients.
The researchers found that compared with the control period, patients' median (midpoint) estimated radiation dose in the follow-up period was reduced by 53.3 percent. An increase in the number of patients receiving the target dose below a certain level (compared with the control period) was achieved at all sites. The increase in the proportion of those reaching the target dose was greatest at low-volume sites (less than 30 scans per month).
"Importantly, despite the reduction in the radiation doses, there were no significant changes during the control period compared with follow-up period in median image quality rating or the proportion of diagnostic-quality scans (554/620 patients [89 percent] in the control period vs. 769/835 patients [92 percent] in the follow-up period)," the authors write.
The most powerful factors associated with achievement of the target radiation dose were the use of lower tube voltage, which increased from 13 percent to 43 percent of cases, and a site study volume of more than 30 scans per month. Among patient-related variables, reduction in heart rate demonstrated a strong positive association with a decreased radiation dose.
"Baseline data obtained in this study support the concern that CCTA testing may result in relatively high radiation doses, but the rapid improvement in radiation dose in the first 3 intervention months demonstrates how use of existing technology and technical methods is associated with dramatically reduced dosages. The dose-reduction program involved an educational aspect at every level in the imaging process. Without a feedback loop of regular dose measurements and reports, similar monitoring of patient preparation, and appropriate imaging protocols and resultant image quality, there would neither be the opportunity to detect dose elevations nor the ability to improve practice," the researchers write.
"The importance of radiation-reduction techniques must be emphasized during physician and technologist training and physicians should demonstrate technical mastery of these methods before certification to oversee CCTA scanning."
-
Radiation dose can be reduced for 'triple rule-out' coronary CT angiography
Apr 03, 2009 |
not rated yet |
0
-
Angled gantry technique reduced breast radiation exposure by 50 percent
Dec 04, 2008 |
not rated yet |
0
-
Newer cardiac imaging machines effective in detecting coronary artery stenosis
Aug 26, 2008 |
not rated yet |
0
-
Coronary CTA costs less than standard of care for triaging women with acute chest pain
Aug 08, 2008 |
not rated yet |
0
-
People without heart disease symptoms should use caution in obtaining cardiac imaging exams
Feb 02, 2009 |
not rated yet |
0
-
Engineers build first sub-10-nm carbon nanotube transistor
Feb 01, 2012 |
4.9 / 5 (33) |
30
-
Something old, something new: Evolution and the structural divergence of duplicate genes
Jan 31, 2012 |
4.6 / 5 (7) |
1
-
The hidden nanoworld of ice crystals: Revealing the dynamic behavior of quasi-liquid layers
Jan 30, 2012 |
5 / 5 (4) |
1
-
Stock market network reveals investor clustering
Jan 27, 2012 |
3.9 / 5 (23) |
8
-
Of microchemistry and molecules: Electronic microfluidic device synthesizes biocompatible probes
Jan 26, 2012 |
5 / 5 (2) |
0
-
Is Everyday Technology Killing Us?
Feb 08, 2012
-
Exercise and weight loss
Feb 08, 2012
-
Why do we have head aches? Our brains can't feel anything.
Feb 07, 2012
-
"The end of diseases" by David Agus, interview from Daily Show with Jon Stewart
Feb 04, 2012
-
Oncolytic adenovirus
Feb 04, 2012
-
Nutrition label stuffs and diets
Feb 02, 2012
- More from Physics Forums - Medical Sciences
More news stories
Overeating may double risk of memory loss
New research suggests that consuming between 2,100 and 6,000 calories per day may double the risk of memory loss, or mild cognitive impairment (MCI), among people age 70 and older. The study was released today and will be ...
Medicine & Health / Neuroscience
4 hours ago |
5 / 5 (2) |
0
|
Starve a virus, feed a cure? Findings show how some cells protect themselves against HIV
A protein that protects some of our immune cells from the most common and virulent form of HIV works by starving the virus of the molecular building blocks that it needs to replicate, according to research published online ...
8 hours ago |
5 / 5 (2) |
0
|
Injured boomers beware: Know when to see doctor
(AP) -- It happened to nurse Jane Byron years after an in-line skating fall, business owner Haralee Weintraub while doing "men's" push-ups, and avid cyclist Gene Wilberg while lifting a heavy box.
9 hours ago |
5 / 5 (1) |
0
Declining health-care productivity in England: Who says so?
Reports that the National Health Service in England has been declining in productivity in the last decade appear to have been accepted as fact. However, a Viewpoint published Online First by The Lancet disputes this. The Vi ...
2 hours ago |
not rated yet |
0
FDA-approved drug rapidly clears amyloid from the brain, reverses Alzheimer's symptoms in mice
Neuroscientists at Case Western Reserve University School of Medicine have made a dramatic breakthrough in their efforts to find a cure for Alzheimer's disease. The researchers' findings, published in the journal Science, show t ...
Medicine & Health / Neuroscience
Feb 09, 2012 |
4.9 / 5 (58) |
17
|
Scientists discover molecular secrets of 2,000-year-old Chinese herbal remedy
For roughly two thousand years, Chinese herbalists have treated Malaria using a root extract, commonly known as Chang Shan, from a type of hydrangea that grows in Tibet and Nepal. More recent studies suggest that halofuginone, ...
New method to examine batteries -- MRI from the inside
There is an ever-increasing need for advanced batteries for portable electronics, such as phones, cameras, and music players, but also to power electric vehicles and to facilitate the distribution and storage of energy derived ...
A mitosis mystery solved: How chromosomes align perfectly in a dividing cell
Although the process of mitotic cell division has been studied intensely for more than 50 years, Whitehead Institute researchers have only now solved the mystery of how cells correctly align their chromosomes during symmetric ...
Google might launch Drive for cloud storage soon
(PhysOrg.com) -- Google's next big move, according to the Wall Street Journal, is a cloud storage service called Drive. Hardly first to the plate, Google is simply catching up to introducing its cloud reposi ...
Lab study raises questions over nano-particle impact
Tests involving chickens have raised questions about the impact on health from engineered nano-particles, the ultra-fine grains commonly used in drugs and processed foods, scientists said on Sunday.
Researchers find extensive RNA editing in human transcriptome
In a new study published online in Nature Biotechnology, researchers from BGI, the world's largest genomics organization, reported the evidence of extensive RNA editing in a human cell line by analysis of RNA-seq data, demons ...