Clowns and party-goers suck helium from balloons to make their voices squeaky, but soon seemingly healthy smokers could inhale it to explore such conditions as emphysema and asthma.
A new test devised by University of Wisconsin-Madison scientists starts with smokers breathing in a liter of the harmless gas, mixed with nitrogen, through a straw and finishes with an MRI that can detect how far the gas has penetrated into the tiny air cavities of the lungs.