A Novel System for Patient Ventilation and Dosing of Hyperpolarized 3He for Magnetic Resonance Imaging of Human Lungs

A versatile ventilator for controlling a patient’s breath cycle and dosing 3He gas has been designed and constructed. It is compatible with a medical magnetic resonance imaging scanner and can be incorporated into routine human lungs imaging procedure that employs hyperpolarized noble gas as a contrast agent. The system adapts to the patient’s lung volume and their breath cycle rhythm, providing maximum achievable comfort during the medical examination. Good quality magnetic resonance lung images of healthy volunteers were obtained. The system has the capability of recycling the exhaled gas to recover the expensive 3He isotope, and can be also adapted to human lung imaging with hyperpolarized 129Xe.