( A faster magnetic resonance imaging (MR...)New MRI technique quickly builds 3-D images of knees

Developed at the University of Wisconsin-Madison, the faster technique will enable clinics to image more patients - particularly the burgeoning group of older adults with osteoarthritis-related knee problems - and can help researchers more rapidly assess new treatments for such conditions.

Magnetic resonance has long been touted as the ideal method for capturing 3-D images of the human body. "But unfortunately, it is kind of a slow technique," says Walter Block, an associate professor of biomedical engineering and medical physics. "You can only sample a few pieces of information needed to build the image at a time."

Consequently, most magnetic resonance technicians acquire images as a series of 2-D slices, which yield high resolution in a single plane and poor resolution in the remaining direction, he says.

To capture an image, a magnetic resonance scanner commonly conducts hundreds to thousands of little "experiments," or encodings, that help to make up the big picture. Block's data-acquisition technique capitalizes on recent magnetic resonance hardware advances that, coupled with a novel way of maintaining a high-level magnetic resonance signal throughout the scan, will speed an MRI session. "But to maintain the high-level signal," he says," you need to be able to complete each of these smaller encodings within a couple of milliseconds."

Rather than using the conventional approach, which sweeps horizontally to gather magnetic resonance data, Block's technique acquires the body's signals radially, in a way that looks somewhat like a toy Koosh ball. "We can essentially acquire data during the whole experiment, where in the (conventional) case, a lot of time was spent either prepping for the experiment or returning it to the
'"/>

Source:University of Wisconsin-Madison