By Steven Reinberg
Thursday, June 7, 2007 12:00 AM
THURSDAY, June 7 (HealthDay News) -- New ways of imaging the heart, the brain and the pelvis could lead to better diagnosis and treatment of illnesses such as heart disease, Alzheimer's disease and ovarian cancer.
That's the assessment of a series of studies presented this week at the Society for Nuclear Medicine's annual meeting in Washington, D.C.
In one study, Dr. James H. Rudd, a cardiologist and scientist with the Imaging Sciences Laboratory at Mount Sinai School of Medicine in New York City, and colleagues showed that using two imaging techniques -- multidetector computed tomography (CT) and imaging positron emission tomography (PET) -- along with N1177, a contrast agent that highlights plaques, provided imaging that was able to determine the amount of inflammation within atherosclerotic plaque and estimate the chances of plaque causing a future heart attack or stroke.
"The idea behind the project was to get an earlier diagnosis of atherosclerosis," Rudd said. "If we can detect these things earlier, then we can start effective therapy earlier and prevent the development of heart attacks and strokes."
Using both imaging techniques together in rabbits gave more information than using them separately, the researchers say. CT imaging helped determine the size of plaque, whether it was causing narrowing of the arteries and whether any inflammatory cells were involved.
The PET scan told the researchers whether the plaques were dangerous and whether they could lead to problems for patients. Using both techniques, they could see not only on the structure of plaque but also the underlying biology of the disease, which could guide and help monitor treatments.
In another study, researchers led by Dr. Cesar A. Santana, an assistant professor of radiology at Emory University, unveiled a new molecular imaging technique that gives a three-dimensional image of the heart, and could significantly improve the diagnosis of heart disease.
Doctors could use this three-dimensional color display to improve the accuracy of diagnosing heart disease and guide treatment, the researchers said.
Another highlight at the meeting was the presentation of the first combined positron emission tomography (PET) images and magnetic resonance (MR) images of the human brain. This technique of taking both images simultaneously represents a leap forward in imaging capabilities, said Dr. Bernd J. Pichler, head of the Laboratory for Preclinical Imaging and Imaging Technology at the University of Tuebingen's Department of Radiology, in Germany.
This type of brain imaging could potentially be the best choice for neurological studies, certain forms of cancer, stroke and the emerging study of stem cell therapy. In addition, PET/MR brain scanning will aid in understanding the pathologies and progression of neurological disorders such as Alzheimer's disease, Parkinson's disease, epilepsy, depression and schizophrenia, the researchers said.
Another study showed that beta-amyloid plaque, which has been linked to Alzheimer's disease, is also associated with brain dysfunction in normal elderly people. This finding provides further evidence that beta-amyloid is related to the fundamental cause of Alzheimer's disease, the Australian researchers say.
Dr. Christopher Rowe, director of the nuclear medicine department and Centre for PET at Austin Hospital in Melbourne, Victoria, found that PET scans could detect the early pathological changes of Alzheimer's disease long before the development of dementia.
There are trials of anti-amyloid drugs under way. If these prove successful, amyloid imaging could have a vital role in identifying people in need of treatment to prevent the development of Alzheimer's, the researchers said.
Another study showed that advanced combined PET and CT imaging can be used to guide the treatment of women with ovarian cancer. Imaging detected more sites of disease and identified women whose disease was likely to progress, Australian researchers reported.
PET/CT imaging influenced treatment decisions in 59 percent of the 90 women by identifying those whose disease was more likely to progress within 12 months, the researchers found. These findings suggest that replacing routine CT scans of the abdomen and pelvis with PET/CT imaging could reduce costs and providing better care for patients, said Dr. Michael J. Fulham, head of the Department of PET and Nuclear Medicine at Royal Prince Alfred Hospital in Sydney.
For more information on CT and PET scans, visit Radiology Info.
SOURCES: June 4, 2007, presentations, Society for Nuclear Medicine annual meeting, Washington, D.C.; James H. Rudd, M.D., cardiologist, and scientist, Imaging Sciences Laboratory, Mount Sinai School of Medicine, New York City