Use of Hyperpolarized 129Xe MR Lung Imaging in Infants

Study Summary

Abnormalities of the lungs are common in newborns and can include aspiration or infectious pneumonia, respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), pulmonary hypertension (PH), congenital diaphragmatic hernia (CDH), and other abnormalities of lung development. Diagnostic radiography is commonly used in this population to differentiate diagnosis and to assess changes after treatment. While X-ray and CT provide quality imaging, they also expose infants to ionizing radiation. MR imaging offers a safe, non-ionizing alternative. However, imaging lungs via 1H MR is intrinsically difficult due to multiple air-tissue interfaces within the lungs causing local gradients and severe magnetic field susceptibility, which leads to an exceedingly short effective transverse relaxation time (T2\*). Additionally, the lungs have low proton density, which along with the short T2\* results in low signal to noise ratio, and the physiological motion caused by respiration and cardiac pulsation further reduces lung signal. The development of more powerful hardware, along with faster MRI techniques, has enabled detailed noninvasive 1H MR imaging of pulmonary tissues. Additionally, the development of inhaled hyperpolarized gas MRI has led to breakthroughs in the ability to visualize and quantify regional ventilation and alveolar size.

Primary Outcome

To calculate the percentage of the lung that is ventilated with 129Xe gas. This is an indicator of lung ventilation. The lung function outcome will be measured using hyperpolarized 129Xe MRI, wherein hyperpolarized 129Xe is inhaled and its distribution is imaged within the lungs. Different MRI pulse sequences are used to obtain different functional information about the lungs. VDP will be assessed using a 2D spoiled gradient echo sequence.

Conditions Studied

Interventions

• DRUG 129Xe

Study Locations (1)