Chest radiograph - Abnormalities. 1  A pulmonary nodule is a discrete opacity in the lung which may be caused by... 2  Neoplasm: benign or malignant. 3  Granuloma: tuberculosis. 4  Infection: roundish pneumonia. 5  Vascular: infarct, varix, granulomatosis with polyangiitis, rheumatoid arthritis.
Helium is used for purposes that require some of its unique properties: its low density, low solubility, and high thermal conductivity. 7,000 tons, or 22%, of the total helium used involves the cooling of superconducting magnets in medical magnetic resonance imaging (MRI) scanners.
Helium-3 is a very rare helium isotope, and you can do MRI/NMR of it. But that is not what happens in typical MRI of humans, as they don't contain any measurable amount of helium-3 (though there seem to be more exotic experiments that use it).he vast majority of helium used in MRI is for cooling, not as an imaging nuclei, to the point that I wasn't aware it was even used in that manner (but if Wikipedia says it, it must be true). The vast majority of helium on the planet is $He^4$, not $He^3$. â Colin McFaul Dec 11 '12 at 16:35.