Related Experiment Video
Updated: Aug 5, 2026
Three-Dimensional Reconstruction for the Whole Lung with Early Multiple Pulmonary Nodules
Published on: October 13, 2023
AI-accelerated 3D gradient echo versus ultrashort echo time MRI for lung nodule detection and measurement
Alexander W Marka1, Kilian Weiss2, Hannah Rosenkranz1
1Institute for Diagnostic and Interventional Radiology, School of Medicine and Health, TUM Klinikum, Technical University of Munich (TUM), Munich 81675, Germany.
Background:
Ultrashort echo time (UTE) sequences are widely used in pulmonary MRI due to favorable lung parenchyma signal but are limited by acquisition time and complex reconstruction.
Purpose:
To compare an AI-enhanced 3D gradient echo sequence with a UTE sequence for lung nodule detection and Lung-RADS classification, using CT as the reference standard.
Materials And Methods:
In this single-center observational study, patients with at least one CT-detected lung nodule underwent pulmonary MRI. MRI included a respiratory-gated AI-accelerated 3D gradient-echo sequence (CSAI-GRE) and a respiratory-gated 3D UTE sequence, both acquired with comparable scan times. Three radiologists independently assessed image quality, nodule detection, and Lung-RADS classification. CT served as the reference standard. Statistical analyses included paired tests for image quality, mixed-effects modeling for lesion-level detection, and κ statistics for Lung-RADS agreement.
Results:
This study included 54 patients (mean age, 65 ± 12 years; 23 women [43%]) with 97 pulmonary nodules. Subjective image quality was higher for CSAI-GRE than UTE (mean score, 4.30 vs 3.91; P = .005). Lesion-level detection was 96.9% for CSAI-GRE and 92.8% for UTE; mixed-effects analysis showed higher conditional detection odds for CSAI-GRE (OR, 10.2; 95% CI, 2.4-43.3; P = .002). MRI-CT agreement for Lung-RADS categorization ranged from substantial to almost perfect across readers (κ range, 0.79-0.93 for CSAI-GRE; 0.72-0.94 for UTE). Lung-RADS reclassification relative to CT occurred in 12.3% (20/162; 95% CI, 8.1-18.3) of CSAI-GRE and 20.8% (33/159; 95% CI, 15.2-27.7) of UTE reader assessments, including 5.6% (9/162; 95% CI, 3.0%-10.2%) and 10.7% (17/159; 95% CI, 6.8%-16.5%) management-relevant changes, respectively.
Conclusion:
CSAI-GRE and UTE enabled reliable pulmonary nodule detection. CSAI-GRE provided superior subjective image quality and slightly higher detection performance than UTE. However, the Lung-RADS reclassification rates suggest that MRI-based Lung-RADS categorization may not yet be sufficiently robust for routine clinical application.
Related Concept Videos
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
01:13Radiological Investigation III: Pulmonary Angiogram and PET Scan
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...