New lung imaging techniques detect emphysema and pinpoint disease faster
Two non-invasive techniques for imaging the way lungs function have been discovered by researchers at the University of Pennsylvania’s School of Medicine.
Radiologists are using hyperpolarized 3He gas to see high resolution images of human ventilation as gas flows in and out of the lungs. To use this powerful research tool, patients must inhale the helium at the exact right time, after it's been exposed to a laser light to make all of the atoms spin in the same direction, creating the polarized helium, which then enters the lung. This enables researchers to measure the rate of diffusion of these helium gas molecules, which reflect the size of the air sacs in the lung. Then researchers can detect very early emphysema, even before it's evident in CT.
"Up until now [we have] been limited by conventional methods which result in rather low resolution images," commented Warren Gefter, MD, chief of thoracic imaging in the radiology department at Penn. "We are developing a way to get a better look inside the lungs by polarizing atoms — making them all spin in the same direction — with magnetic resonance (MR), which allows the atoms to have a strong signal for sharper images."
Another MR technique allows Penn imaging researchers to see down to the cellular and intracellular level of the lung. Investigators have figured out a way in which they hope to look for a "marker" of disease inside the body. In animal models, they are injecting polarized carbon-13-labeled molecules, watching its conversion, and taking images as it breaks down and releases energy. What this 'flagged molecule' converts into as it moves throughout the body could tell us whether the cell is normal or abnormal and pinpoint the location of disease. Penn researchers hope to translate this technique for use in humans before the end of 2007.