Potential of Apparent Diffusion Coefficient values in Solitary Pulmonary Nodules Imaging at Low-Field MR: A 0.55/1.5T Scanner Comparison

Motivation: Clinical implementation of Solitary Pulmonary Nodules (SPNs) DWI at Low-field (LF) MR were rare, related to inconsistent standardization and lack of clinical validation of ADC cutoffs. Goal(s): To explore the potential of ADCs at LF MR to differentiate benign and malignant SPNs. Approach: ADCs of SPNs were measured from 0.55T/1.5T images respectively. Subsequent biopsy or excision pathologic results were treated as gold standard for diagnositic metrics to explore ADC distributions and cut-offs. Results: ADCs of malignant nodules was lower than benign one at 0.55T while without significant difference at 1.5T. Sensitivity and specificity of ADCs for differentiating SPNs were 78.4% and 78.6%. Impact: ADC cut-offs of 0.55T MRI can be feasibly integrated into clinical suspected SPNs interpretations, demonstrating the potential to decrease overall biopsies in future while further valid conclusions are still needed through well-designed and larger clinical trials.