June 1, 2008 New technology allows cardiologists to capture detailed pictures of the heart in less than one second, revealing subtle changes in blood flow and blockages in tiny blood vessels. This machine sends x-rays through the bodies, which are picked up by 320 different detectors then digitized and processed by computers to compile an extremely detailed image.
The latest generation of CT scanners is here, capturing pictures of whole organs in seconds!
John DeFord has an arrhythmia -- a heart condition that slows down life a little. "So I can walk on a treadmill, but I can't run," DeFord told Ivanhoe. "I can exercise, but not vigorously."
Today, his condition is being fixed, but first, cardiologists need a picture of his heart. Now, a new CT scanner -- one of the most powerful in the world -- can capture an image in less than one second! "The most unique part is taking a picture of the heart in one heartbeat or less," Richard George, M.D., a cardiologist at Johns Hopkins University in Baltimore, told Ivanhoe.
The new scanner collects enough data to produce a three-dimensional image of almost any organ in the body. "One of the most exciting things is getting a more accurate image that is easier to analyze and an image that we trust our results that we're reporting," Dr. George explains.
The new scanner can produce 320 -- or an even more detailed 640 -- cross-sectional images or slices. Then, a computer stacks up the slices to create 3-D pictures. Doctors can better see subtle changes in blood flow or blockages forming in tiny blood vessels in organs, with amazing detail and accuracy.
The one second scan exposes patients to less radiation and allows more patients to receive the scan. DeFord's heart scan is being used as a guide to help speed up his life. "I'm hoping to get my life back," he says. Now, getting it back can take just seconds.
The new 320 slice CT is only located in two places in the United States: Brigham and Women's Hospital in Boston and Johns Hopkins Hospital in Baltimore.
WHAT IS ARRHYTHMIA? An arrhythmia occurs when the heart beats too fast, too slow, or irregularly. This keeps the heart from pumping blood properly. Normally, the heartbeat starts in the right atrium, when a special group of cells (the "pacemaker" of the heart) sends an electrical signal causing the muscles to contract. These signals travel through connecting fibers to all parts of the ventricles, and must follow the exact route in order for the heart to pump properly.
There are many types of arrhythmia, identified by where they occur in the heart (in the atria or ventricles), and by what happens to the heart's rhythm when they occur. One example is atrial fibrillation, an irregular heartbeat that interferes with the heart's ability to pump blood. Abnormal electrical signals cause the atria, or upper chambers of the heart, to contract erratically. Blood then pools in the atria and forms clots. These can travel to the brain and cause a stroke. The most serious arrhythmia is ventricular fibrillation, where the lower chambers quiver and the heart can't pump any blood. This results in collapse and sudden death -- if there isn't immediate medical attention.
HOW CT SCANS WORK: CT scans use X-rays to image the body. X-rays can pass through most materials. It all depends on the size of the atoms that make up the material; larger atoms absorb X-ray photons, while smaller atoms do not, and the X-rays pass right through. For instance, the soft tissue in the body is composed of smaller atoms, so it doesn't absorb X-rays very well. But calcium atoms in the bones are much larger and do absorb X-rays. A camera on the other side of the patient records the patterns of X-ray light passing through the patient's body. In a CT scan, a series of X-ray beams is directed through the body from different angles. This creates cross-sections so scientists can get a better view of the body. The images are put together by computer into a stack of pictures that can be viewed rapidly, like flipping through a deck of cards.
The American Association of Physicists in Medicine contributed to the information contained in the video portion of this report.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.