(dailyRx)
Study researchers have unveiled a new type of imaging technology capable of diagnosing heart disease by measuring ultrasound signals from molecules that are exposed to a quickly-pulsing laser.
Indiana-based Purdue University investigators said the new method can take precise three dimensional images of plaques lining arteries. Traditional imaging technology capable of providing molecular information are not able to penetrate deep enough into the tissue to reveal those three dimensional plaque structures.
Previously only cutting an artery cross section could show those three dimensional structures, but the technique was not possible for living patients. Additional technology that allows those structures to be viewed will help physicians make better diagnoses.
The imaging uses nanosecond laser pulses in the near-infrared range of the spectrum. The laser is able to generate molecular vibrations not absorbed by the blood, while the pulsing laser forces tissue to heat and expand locally. This generates pressure waves that can be picked up with a transducer at the ultrasound frequency.
In viewing the images, researchers could see the presence of carbon-hydrogen bonds making up lipid molecules in arterial plaques that cause cardiovascular disease. It is possible the method might also be useful in detecting fat molecules in muscles to diagnose diabetes and other disorders, including neurological conditions and brain trauma. The images also reveal nitrogen-hydrogen bonds making up proteins that would be useful in diagnosing a host of other diseases and studying collagen’s role in forming scars.
Investigators hope they can construct a miniature version of the system, which would allow construction of an endoscope to put into blood vessels using a catheter, which would allow them to view the exact nature of the plaque formation in the walls of arteries.
The research, funded from the National Institutes of Health and the American Heart Association, was based on research with pig tissues in laboratory samples and also with live fruit flies.
Coronary Artery Disease
Coronary artery disease is the leading cause of death in the United States and in the rest of the world. Estimates point to almost one half of all middle aged men and one third of all middle aged women in the United States developing some form of CAD. The primary symptom of angina, commonly known as chest pain, occurs when the artery is almost completely blocked.
Plaques made up of cholesterol and fibrous tissue lodge in the walls of the arteries that supply blood to the heart. Slow growth of the plaques can cause chest pain as they restrict blood flow to the heart muscle, and complete closure or rupture of the plaque can cause a myocardial infarction, commonly known as a heart attack, with resulting disability or death. CAD is primarily a disease of diet and habits, with the greatest risk factors coming from smoking, high blood pressure, high cholesterol, and diabetes.