Daijiworld Media Network – New Delhi
New Delhi, Jul 3: Low-field MRI could emerge as a radiation-free alternative for monitoring patients with pulmonary sarcoidosis by assessing both structural lung changes and regional lung function, according to a new prospective study.
Researchers said that while chest CT remains the gold standard for detecting structural abnormalities, low-field MRI provides additional functional information that correlates with pulmonary function tests, making it a promising option for long-term follow-up in selected patients.
Sarcoidosis is an inflammatory disease characterised by the formation of granulomas that can affect multiple organs, with the lungs being the most commonly involved. In some cases, the disease may progress to irreversible pulmonary fibrosis. Since many patients require repeated imaging, reducing exposure to ionising radiation is an important consideration, particularly among younger individuals.
The study evaluated the feasibility and diagnostic performance of 0.55-T low-field lung MRI in 15 patients with pulmonary sarcoidosis and compared the findings with 30 healthy volunteers. Researchers combined structural imaging with functional proton MRI to assess regional ventilation and perfusion, using chest CT as the reference standard.
MRI demonstrated the highest sensitivity in detecting lung consolidations at 86 per cent. It showed moderate sensitivity for identifying nodules (67 per cent) and ground-glass opacities (70 per cent), while its performance was lower for reticulations (29 per cent) and traction bronchiectasis (27 per cent) compared to CT. The study also reported moderate agreement between readers and between MRI and CT findings.
Functional MRI revealed significantly higher ventilation defect percentage (VDP), perfusion defect percentage (QDP) and ventilation-perfusion overlap (VQO) in patients with pulmonary sarcoidosis than in healthy volunteers.
The functional measurements also showed a strong association with lung function tests. Ventilation defect percentage was strongly correlated with the residual volume to total lung capacity (RV/TLC) ratio, while perfusion defect percentage correlated with forced expiratory volume in one second (FEV1).
Researchers concluded that low-field MRI offers a radiation-free approach that combines structural and functional assessment of the lungs. Although it cannot yet replace CT for detecting all structural abnormalities, it may serve as a valuable complementary tool for monitoring disease progression and reducing radiation exposure during long-term follow-up.