Fig. 7
From: Multi-nuclear magnetic resonance spectroscopy: state of the art and future directions
Reproduced with permission from Elsevier Ltd (License Number: 5324281420540). J Allergy Clin Immunol. 2003 Jun;111(6):1205–11
Coronal MR images obtained immediately after inhalation of hyperpolarized Helium-3 gas in a healthy normal volunteer (a) and in patients with mild (FEV1 of 132% of predicted value. b Moderate (FEV1 of 83% of predicted value. c Severe (FEV1 of 34% of predicted value. d Asthma. The distribution of the gas is homogenous in the normal volunteer, and ventilation defects are seen with increasing numbers in the asthmatic patients with increasing severity (arrows pointing at several defects).