Use of Hyperpolarized 129Xe MR Lung Imaging in Infants
Status:
Recruiting
Trial end date:
2023-04-30
Target enrollment:
Participant gender:
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.