Repeatability in Hyperpolarized 3-Helium With MRI

Repeatability in Hyperpolarized 3-Helium Magnetic Resonance Imaging

The main purpose of this study is to assess and test the reproducibility and results of hyperpolarized 3-Helium gas as a contrast agent with Magnetic Resonance Imaging (MRI) of the lungs in healthy adult subjects.

New CT imaging techniques often expose the patient to higher doses of radiation. There is a great deal of concern about effects of medical radiation exposure on the general public and regulations are becoming stricter on the radiation doses that are allowed.

One novel procedure that has been developed to evaluate the function and structure of the lung is the use of hyperpolarized gases with MRI scanners. We want to compare the lung imaging techniques that we have developed in our lab to a technique that uses hyperpolarized 3-Helium gas with MRI. This technique is free from radiation and less invasive than many lung imaging techniques.

Hyperpolarized gas MRI is based on the introduction of spins into the lungs, allowing imaging to take place. The use of hyperpolarized 3-Helium has a few advantages:

1. it allows us to see the microstructure of the lungs through diffusion imaging (apparent diffusion coefficient) which correlates with the size of airways and alveolar space.
2. it allows us to see ventilation, or how air moves in the lungs, at a high resolution.
3. it is capable of ultra fast imaging which will help us assess gas flow patterns within the airways.

and 4) the speed of depolarization lets us measure the partial pressure of oxygen and associated gas exchange mechanisms.

Inclusion Criteria:

• must be between the ages of 18 and 90
• must have a Body Mass Index (BMI) of < 32 and weigh < 200 lbs.

Exclusion Criteria:

• if female, must not be pregnant or breastfeeding
• must not have any metal objects in or on their body including body piercings that cannot be easily removed, bullets, metallic fragments or slivers in eyes, skin, etc., pacemaker or defibrillation, aneurysm clips, cochlear implants, coronary stents, or neurostimulation.
• must not have a history of claustrophobia, panic disorders, anxiety attacks, atrial fibrillation, uncontrolled high blood pressure, frequent ventricular ectopic rhythm, hemodynamic instability, kidney dysfunction or heart disease.