Comparison of diagnostic quality of 3D ultrashort-echo-time techniques for pulmonary magnetic resonance imaging in free-breathing

• Published in: Acta radiologica (1987) 2023-05, Vol.64 (5), p.1851-1858
• Main Authors: Metz, Corona, Weng, Andreas Max, Böckle, David, Heidenreich, Julius Frederik, Slawig, Anne, Benkert, Thomas, Kraus, Sabrina, Köstler, Herbert, Veldhoen, Simon
• Format: Article
• Language: English
• Subjects: Humans; Imaging, Three-Dimensional - methods; Lung - diagnostic imaging; Lung - pathology; Magnetic Resonance Imaging - methods; Pleural Effusion; Prospective Studies; Respiration
• ISSN: 0284-1851; 1600-0455
• DOI: 10.1177/02841851231151366

Background Ultrashort-echo-time (UTE) sequences have been developed to overcome technical limitations of pulmonary magnetic resonance imaging (MRI). Recently, it has been shown that UTE sequences with breath-hold allow rapid image acquisition with sufficient image quality. However, patients with impaired respiration require alternative acquisition strategies while breathing freely. Purpose To compare the diagnostic performance of free-breathing three-dimensional (3D)-UTE sequences with different trajectories based on pulmonary imaging of immunocompromised patients. Material and Methods In a prospective study setting, two 3D-UTE sequences performed in free-breathing and exploiting non-Cartesian trajectories—one using a stack-of-spirals and the other exploiting a radial trajectory—were acquired at 3 T in patients undergoing hematopoietic stem cell transplantation. Two radiologists assessed the images regarding presence of pleural effusions and pulmonary infiltrations. Computed tomography (CT) was used as reference. Results A total of 28 datasets, each consisting of free-breathing 3D-UTE MRI with the two sequence techniques and a reference CT scan, were acquired in 20 patients. Interrater agreement was substantial for pulmonary infiltrations using both sequence techniques (κ = 0.77 − 0.78). Regarding pleural effusions, agreement was almost perfect in the stack-of-spirals (κ = 0.81) and moderate in the radial sequence (κ = 0.59). No significant differences in detectability of the assessed pulmonary pathologies were observed between both 3D-UTE sequence techniques (P > 0.05), and their level of agreement was substantial throughout (κ = 0.62–0.81). Both techniques provided high sensitivities and specificities (79%–100%) for the detection of pulmonary infiltrations and pleural effusions compared to reference CT. Conclusion The diagnostic performance of the assessed 3D-UTE MRI sequences was similar. Both sequences enable the detection of typical inflammatory lung pathologies.