Pulmonary UTE Signal Intensity Normalization using Anatomical References

Motivation: UTE MR signal intensity (SI) distributions within the lung are not standardized across patients or over time. Goal(s): To develop a pulmonary UTE SI normalization method using anatomical references and implement the normalization method in idiopathic pulmonary fibrosis patients. Approach: SI within the lung is normalized to the median trachea and aorta SI as reference standards for pure air and blood; signal bias fields are generated using spline fit to tissue signals outside of the lung. Results: Corrected lung measures were consistent over time and were increased in more severe disease. Impact: This method may be used to develop quantitative parenchymal density measures on UTE MRI as a biomarker to assess cross-sectional differences in disease populations, disease progression and treatment response without the ionizing radiation inherent to gold-standard computed tomography.