Diffusion-weighted magnetic resonance imaging of spinal bone marrow

Area of Science:

• Radiology
• Medical Imaging
• Biophysics

Background:

• Diffusion-weighted (DW) imaging offers an alternative contrast mechanism in medical imaging.
• It quantifies the random motion of water protons at a molecular level.
• Various imaging sequences facilitate DW imaging, including steady-state free precession, navigated spin-echo, and single-shot echo planar imaging.

Purpose of the Study:

• To evaluate the utility of intravoxel incoherent motion (IVIM) analysis of water protons in differentiating benign from malignant spontaneous vertebral fractures.
• To assess the signal characteristics of acute benign osteoporotic fractures and metastatic fractures on DW sequences.

Main Methods:

• Utilized diffusion-weighted imaging (DWI) sequences to analyze water proton motion.
• Applied intravoxel incoherent motion (IVIM) analysis for differential diagnosis.
• Compared signal intensities on DW sequences between benign and malignant vertebral fractures and normal bone marrow.

Main Results:

• Acute benign osteoporotic fractures exhibited hypo- or isointense signals on DW sequences, indicating persistent free water proton mobility and significant signal loss with increasing diffusion strength.
• Metastatic fractures demonstrated hyperintensity compared to normal bone marrow, suggesting altered water proton mobility within neoplastic tissue.

Conclusions:

• Intravoxel incoherent motion (IVIM) analysis of water protons is a valuable tool for the differential diagnosis of spontaneous vertebral fractures.
• DW imaging shows potential in differentiating benign from malignant vertebral lesions based on water proton mobility.
• Further research is needed to explore the capability of different DWI methods in characterizing other bone marrow alterations.