Radiation-free assessment of lung function and structure in infants and toddlers with chronic respiratory diseases using magnetic resonance imaging

Background: The assessment of lung function and structure in infants and toddlers is highly limited due to the constraints of existing lung function and imaging techniques. Common lung function methods such as spirometry are not feasible in this age group, and research methods are very sophisticated and not widely available. Chest X-rays lack sensitivity for detecting subtle respiratory changes, and radiation burden of computed tomography limits its utility in this vulnerable age group. Conversely, magnetic resonance imaging (MRI) offers a radiation-free alternative with superior soft tissue contrast, making it a crucial tool in diagnostic medicine. In recent years, MRI has emerged as a non-invasive lung imaging modality and shown excellent sensitivity for the assessment of structural or functional lung impairments. However, MRI of the lung is rarely performed in infants or toddlers as it presents unique challenges compared to imaging older children or adults. The small size of infant lungs requires improved spatial resolution for adequate visualization of anatomical structures, whereas rapid respiratory and cardiac cycles necessitate rapid image acquisition or efficient gating techniques. Hence, there is an urgent need for the development of non-invasive and radiation-free diagnostic techniques for lung imaging in the youngest patients.

Aims and Methods: We aim to develop and validate novel proton-based and contrast-agent free MRI techniques for assessing lung impairment in infants and toddlers with chronic respiratory diseases and age-appropriate settings for lung MRI without general anesthesia. To achieve this, we will build upon our previous expertise in lung imaging using functional MRI in children. The project will focus on developing non-Cartesian steady-state free precession imaging techniques to improve spatial-temporal resolution, addressing the unique physiological conditions in young patients, as well as adaptation of our current techniques for morphological lung imaging. An important part of this project is the translation of this specialized MRI methodology into clinical application for improved scalability and seamless integration info clinical workflows. We will develop the optimal settings for lung MRI during natural sleep or with slight sedation only. Eventually, we will evaluate the new age-adapted lung MRI techniques in healthy infants and toddlers and in patients with different lung diseases including prematurity with and without bronchopulmonary dysplasia, cystic fibrosis and others. 

Significance and Broader Impact: In contrast to conventional radiographic modalities, the proposed MRI techniques will allow a radiation-free and non-invasive functional and structural assessment. This addresses a critical gap in current diagnostic capabilities and has the potential to change current clinical and research approaches. The ability to safely and repeatedly assess lung function and structure in young children could significantly advance our understanding of early lung development and the pathogenesis of various respiratory diseases. This could lead to earlier detection and earlier intervention in pediatric lung diseases, potentially improving long-term outcomes. The integration of these techniques into clinical workflows will improve patient care, guide treatment choices, predict disease progression, and support the development of individualized therapeutic measures. 

In conclusion, this project will advance the field of pediatric lung imaging by providing a safe, effective, and scalable diagnostic tool, ultimately improving our understanding and management of early lung diseases. Developing MRI techniques tailored for infants and toddlers will offer new perspectives on the early stages and advancement of chronic respiratory diseases, ultimately enhancing patient care and outcomes.