Morphometric analysis of black bone MRI for radiation-induced bone injury in the head and neck

Motivation: To address the unmet need to accurately visualize cortical bone via current MR standard imaging methods. Goal(s): To develop a morphometric analysis of black bone MRI; a low-flip angle sequence that captures cortical bone comparable to CT. Approach: We obtained CT, T2-weighted, and black bone MRI scans from 15 head and neck cancer patients. Mandibles were manually segmented; dice similarity coefficient (DSC), mean distance to agreement (MDA), and volumetric analysis were evaluated. Wilcoxon signed-rank test checked for statistical significance. Results: Black bone vs. T2-weighted MRI had improved DSC (0.868/0.722), MDA (0.0787/0.182), and volumetric accuracy (-3.95%/-9.37%) using CT as reference. Impact: Black bone MRI shows promise in cortical bone visualization, which has direct potential to detect early anatomical changes caused by radiation. Its sub-millimeter voxel size allows for enhanced spatial resolution compared to standard-of-care CT and T2-weighted MRI.